What does climate change mean for New York City?

Impact of climate change on New York City’s coastal flood hazard: Increasing flood heights from the preindustrial to 2300 CE

Andra J. Garner, Michael E. Mann, Kerry A. Emanuel, Robert E. Kopp, Ning Lin, Richard B. Alley, Benjamin P. Horton, Robert M. DeConto, Jeffrey P. Donnelly, David Pollard

Data and Methods: This study employs various models to understand the future impact of climate change from tropical cyclones. These cyclones create storm surges, which are abnormal rises in water that often lead to flooding. To model storm surge heights in the past (1970-2005), this study uses data from about 5,000 storms. For predicting future storm characteristics for the next few centuries, the study assesses about 12,000 storms. Researchers use storm data to run a variety of simulations that have varying parameters. For example, they can modify the trajectories and wind speeds of tropical cyclones, and the frequencies and intensities of storms to model different scenarios.

They then used the storm models to quantify potential flooding in New York City by combining estimates of storm surge heights with anticipated sea level rise. Such changes in sea level are governed by mass loss of glaciers and ice sheets, thermal expansion, ocean dynamics, and water storage on land. Again, they modified these parameters in a number of models to predict flooding from future storm surges. This study focuses on two specific scenarios from previously developed models: Representative Concentration Pathway (RCP) 4.5 and 8.5. Various modifications to RCP4.5 and RCP8.5 are used to make predictions about the future of storm-related flooding in New York City.

FIgure 1. Projected sea level rise from present day to 2300. Climate projections RCP4.5 (yellow) and RCP8.5 (orange) have much lower projections than the red and maroon projections that represent enhanced Antarctic Ice Sheet melt. By 2300, sea level near New York City could rise by a maximum of 15.7 meters (51.5 feet).

Results: This group found that the maximum wind speeds of tropical cyclones in the future are much greater than the maximum speeds we see today. From this they conclude that future tropical storms will be much more intense, and the storm surges that reach New York City will be greater. They also found that the tracks of tropical cyclones will shift with time, and the density of tracks near New York City will increase.

For the next century, this study estimates sea level rise for New York City to be between 0.55 and 1.4 meters (Figure 1). From 2100 to 2300, they predict possible rises of 1.5 to 5.7 meters. If they increase the potential ice loss from the Antarctic Ice Sheet, those values drastically increase to a maximum sea level rise of 15.7 meters by 2300. Remarkably, these values simply estimate relative sea level rise without the added effect of storm surge. Toward the end of this century (2080 to 2100), flood heights are expected to be 0.7 to 1.4 meters higher than modern New York City floods (Figure 2). By 2300, storm surges could cause floods that are 2.4 to 13.0 meters higher than modern values.

Figure 2. These four different models show flood height versus density. Each model compares modern heights to RCP4.5, RCP8.5, and both scenarios with enhanced Antarctic Ice Sheet melt. With all models and all scenarios, the average flood height is expected to increase.

Why is this study important? At present, an increase in the intensity and frequency of storms would have a negative effect on coastal zones like New York City. However, in a future with higher sea levels, the effects of tropical cyclones and storm surges could be catastrophic. Continued emissions of greenhouse gases, rising temperatures, and consequential melting of ice will create a future with significantly higher sea levels. As storms develop and create surges of higher water, their resulting floods will be larger than anything New York City–or any other city–has seen before. Comprising of nearly 50 million built square meters and over 8 million people, this coastal city is a climate change target. The hazards associated with sea level rise in such a large and populous area are unimaginable. This study only looked at the effects on this one city; but there are places around the world that risk losing everything to climate change and sea level rise.

The big picture: Sea level will rise as human-driven climate change continues to warm global temperatures and melt ice sheets. The combined effects of higher sea levels and more intense tropical cyclones will create storm surges with the potential for catastrophic flooding in major cities like New York.

Citation: Garner, A.J., Mann, M.E., Emanuel, K.A., Kopp, R.E., Lin, N., Alley, R.B., Horton, B.P., DeConto, R.M., Donnelly, J.P., and Pollard, D., 2017. Impact of climate change on New York City’s coastal flood hazard: Increasing flood heights from the preindustrial to 2300 CE. PNAS. DOI: 10.1073/pnas.1703568114

Applying to Graduate School

Maggie here-

I am finishing applying to grad schools for my Ph.D. and figured some of you might also be currently applying to graduate programs or starting to think about if you want to pursue a Master’s degree or a Ph.D. My main goals for this post are sort of two-fold: what is the process of applying to graduate programs and how do you stay sane while applying. So let’s get to it!

Key aspects of this post

  • Look for people and research that interests you, not just locations
  • Contact people at the school that you would want to work with-this is key! Look for people whose work interests you and start contacting them early-ask if they are taking students, what kind of research they do, what it would entail, etc.
  • Communicate with friends, professors, etc. if you need help with your statements or even just someone to say I know this sucks!
  • Make time for yourself-do things that aren’t related to applying to schools and have fun!
  • No matter how daunting and stressful this is, you are capable of doing this!

How to Apply for Grad School

Applying for grad school is very different from applying to undergraduate programs and unfortunately a lot less intuitive. When you were in high school (or shortly after) and applying to colleges there were a lot of people who were around to help you navigate applications and there may have only been one application you needed to fill out to send to many schools. You could also choose colleges based on what state or even which city you wanted to be in for the next four years.

Grad school is very different in that you are looking for specific research programs and people that you want to work with, rather than a location. The location can sometimes be a driver for your research, but in most cases that really is one of the last things that plays a role in your decision to apply there. Grad applications are also more short statement driven; you will be asked for statements of purpose (why do you want to come to this school), personal history statements, and the ever vague “additional statements.”

Statement of Purpose

This statement really is the meat of your application. What has made you decide to go to grad school, what do you want to study, why do you think this school and this advisor is the only place that you can learn what you want to learn. This statement can be totally daunting because often there are no directions or clarifying statements about what to include. I personally like to include a quick paragraph that is more of a narrative- what experience in science did I have that has stuck with me and made me want to be a scientist as an adult? Did you go to a cool summer camp or have an awesome science teacher? Something to show your background and make you a human can make your statement easier for you to write and easier for people to read. After that paragraph is your chance to wow them- what super cool research have you done, do you have a research question that you just have to know the answer to? How does this advisor and school help you reach your research and personal goals? This statement really is up to you to decide which direction you take it in, just make sure that if a school does want you to address something specific in this statement that you answer it!

Personal History Statement

The personal history statement is a place for you to go a little more in depth with personal experiences that you have had (positive or negative) that have led you to where you are today. It can be family or personal matters, or even research experiences that you feel have shaped your career trajectory. In this statement you can also address any “problems” in your transcripts or academic records. If you do choose to address something that was a challenge to you or something that impacted you negatively, try to keep positive language throughout. How did you overcome these challenges, what did you learn about yourself with this challenge, etc. Grad schools and advisors want to know who you are now, not who you were your first semester freshman year. If you have something in your transcript that you want to address and a personal history statement isn’t asked for, I have also asked a trusted letter writer to discuss that in my letter. The personal history statement is a chance for you to show how much you shine, even in the face of adverse conditions.

Other Documents

This upload button can cause a lot of grief because it will literally say “other documents.” Don’t panic, this is not required and you don’t have to upload something if you don’t have something else you want to add. If you know you want to be a professor and you have already had some teaching experience so you have a teaching philosophy or want to learn how to teach more effectively, that could be a statement you might add. If you love doing outreach and you feel very strongly that you can bring something to the table with your outreach efforts, you can add a statement about that. I just submitted my first “other document” with my Ph.D. applications and I only submitted it because I feel very strongly about the importance of teaching and outreach and wanted to share that side of myself with the schools I was applying to. If you don’t feel like you need to share anything else with the schools, don’t. It’s not something to stress too much over, because this whole process is stressful enough!

How to stay sane while applying

As someone who is currently applying for grad schools, this is 100% the hardest part for me. Even though I have really supportive family and lab mates who read over every statement that I write, the process can still feel very overwhelming. You have worked so hard for so long and you just want these people you have talked to to see how great you are and be deemed worthy enough to work with them. The best advice I can offer is to surround yourself with friends. Some of them may have done this before or are in the process of doing this with you, take the time you need to talk about applications but don’t let it consume your life. Spend time with people away from computers, go do fun things, remind yourself that life isn’t just about school. Take walks during the day-I spend ~8 hours a day sitting at my desk and a lab bench and I have found that taking a walk with my friends during the day can be just what I need to feel refreshed and ready to keep working. Play with animals-my cat has been a very big help in this application process because he provides so much comic relief! Play music that boosts you up and makes you feel good-this past week my lab group had a jam session to the Moana soundtrack. If that isn’t love and support, I don’t know what is!

Mock United Nations Climate Negotiations Game

Andy here-

A key question for society is how do we transfer the ability to understand other people’s perspective, to value one another? How do you teach somebody to care about other people?

I tackled that in a physical science class this semester. Since I teach Historical Geology, we spent time on climate change. Specifically, I implemented a climate change game in the class in which the students organize and lead a mock-United Nations climate negotiation.  The exercise is designed to teach students climate awareness and the impacts of climate change on the global system. All of the materials to teach this exercise are available online for free.

At the end of our exercise one student wrote:

I learned that if we don’t start making changes right now, developing countries will be at risk.

I feel motivated to make changes. I will try to reduce my CO2 emissions and advise others to do the same.

Want the same outcome and understanding from your students? Here’s how:

I teach a 60 or 30-student Historical Geology course at Sam Houston State University. It covers a multitude of different subjects; from evolution, to the birth of the solar system, to the climate system. One of the aspects of climate science that I wanted the students to leave with was an appreciation for modern climate change, and how it affects individuals in developing countries (this course was taught in a Hurricane Harvey affected region). While this course doesn’t shy away from controversy, this is the first time that we had to address our modern political (ir)reality head-on.

Our activity was a mock-UN climate negotiation game. World Climate Simulation is a well-respected activity. It’s been used in a number of different contexts from high schools to practicing for UN negotiations, and is available in several different languages.

In my course we played the 6-region version. There were delegations from the United States, European Union, Other Developed Countries (Russia, Australia, etc.), China, India, and Other Developing Countries. Each student gets a page (front and back) write up about their region and its position on climate related issues.

The goal of the exercise is to keep the world to 2°C of warming and to have $100 billion in the Green Climate Fund. Using this game in class gives students a taste for the complicated nature of these negotiations and an understanding of how the climate system works. The game in particular highlights the difficulty of being in a developing nation, by making abundantly clear the inequity between groups. The students also see, by experimenting themselves, how quickly emissions have to peak and reduce to keep us at 2°C. Gaming wise, in the end, the students should get that the key is to reduce the consumption of developed nations, and for those nations to include enough money into the Green Climate Fund to allow the developing nations to skip the fossil fuel age.

Here’s how the game works in practice

The facilitator (the teacher/instructor) opens the summit with an address asking the delegates to feel the full weight of their duties, and to consider the world they would like their children to live in. Then, they attempt set several positions:

  • Year to peak emissions
  • Year to begin reducing emissions
  • Yearly percentage of reductions
  • Contributions to the green fund

After the group sets their initial position they begin arguing with the other groups. After 20-25 minutes the summit reconvenes, the facilitator asks them to present their positions in 2 minutes each. Then there is a discussion of if they think they have made it. Lastly, their positions are transferred to C-ROADs, a complicated-enough climate model (click here for model), and the delegates can see how they did.

I had two helpers help me facilitate the course, Time Scavengers Editor in Chief Susanna Fraass and an upper-level geology student. They were most helpful the first day, as set up can be overwhelming when you’ve got 60 irritable undergrads. Each group has a placard to show their area. The more developed countries get snacks and tablecloths, while the Developing nations have to sit on a tarp. In one section the India delegation got a table and no chairs, while the Chinese delegation got too few, so several had to stand. Susanna walked around the room recording interesting events or statements from students while the upper-level geo student either made mischief as a fossil-fuel representative or helped with running C-ROADs and ensured everybody was ‘on-task’.

Group dynamics obviously play a big role in this. I found that in the smaller class ~5% of the students opted out and just played on their phones, while in the bigger one it was closer to 15-20%. I made attendance for the week of the negotiation 5% of their grade, so there were students that were less than enthusiastic about being in class who normally skip. In the coming semester I will probably have a few of the students in the larger class play the two lobbies, Environmental and Fossil Fuel, in order for them to have more to do. 10 students-per group was too many. The Fossil Fuel Lobby gets candy to sway emissions levels, while the Environmental lobby gets to make signs and organize a demonstration.

The way that the two iterations of the game preceded was very different. The 30-student class ended up modeling how climate negotiations proceed in 2017, while the 60-student class modeled circa-2015 negotiations. In the 30-student class, the US stayed at their table in the back of the room requiring other students to come up to them to discuss policy. When discussing policy, they were inflexible in their positions, even going so far as to attempt to run a scam on the Developing Nations. The US told the Developing Nations they would reimburse them for their additions to the Green Climate Fund (the developing world is to be the recipient of those funds, not pay in). They made a big statement about how they were going to engage their philanthropic community and advocate for individuals from the US to donate. None of that actually is included in the game, so it was in essence, ‘hot air’. In that vacuum the EU stepped in and attempted to lead negotiations with the rest of the world, though somewhat ineffectively. That is not a comment about the ability of the EU to negotiate in that class, one student in particular was giving her all. It’s more an observation that the ire in the room was directed at the US and most actions seemed to be inspired by anger in the directions of the US representatives roleplaying the Trump administration.

In the 60-student class the US took an active role in negotiations, mirroring the Obama administration’s more active role. In the middle of the second round of negotiations the US hosted a miniature G-20 summit behind their table, or a ‘G4’ where the US, EU, Developed Nations, and China tried to hammer out a deal. A EU representative found the website for the climate model and she was attempting to solve the problem for their maximum benefit while still trying to keep to 2deg C. She quickly reached a conclusion and then led her group in refusing to budge from their initial bargaining position. Though their initial position was fairly aggressive with its targets, the rest of the class did not agree with their inflexibility. Their inability to write their position on the board correctly also was met with shouts of displeasure from the other delegations.

The larger class also made for some more entertaining shenanigans. China, apparently unsatisfied with their ‘G4’ deal, changed their position on the board after seeing the other’s contributions to the Green Climate Fund. The room exploded in shouts, 30-40 students were pointing at each other while watching the transcription of positions onto the chalkboard. India and the US got into a shouting match with a representative from India saying, “We’re just trying to feed our people!” and the US representative throwing up his hands saying, “I’m just telling you what we need to have happen, man.” The Developing Nations, sitting on the ground in front of the board, snuck in to change the Green Climate Fund, adding a zero to a group’s contribution. The game builds in tension, and having to stretch it over multiple periods dissipates that tension, unfortunately.

Neither class solved the problem, but they got to 2.4 °C and both had 100-110 billion dollars in the Green Climate Fund. That’s far better than the real negotiations, as they’ve gotten us to 3.4 °C and ~10 billion. The quick influx of money makes it apparent that the students do not really fully understand the massive sums of money that are required within that fund, as they rather quickly built that up. From a purely gaming standpoint, the goal of the Green Fund is that the Developing Nations require massive capital investments to skip over the fossil fuel age. If the US, EU, and Developed Nations add money in too quickly, then the leverage for the Developing Nations is gone. It misses the difficulty of trying to decarbonize the developing nation’s economy.

At the end, there’s a discussion of why peaking emissions now is key to solving the problem, how the Green Fund money gets distributed, among other aspects. After I talked for a bit I had them talk through their positions, if they had individual goals while engaging in the game. This didn’t really work, but it did give me a chance to talk about the differing US positions in the different classes.


I had all the students write answers to three prompts:

1. What did you learn?

2. How do you feel?

3. What actions will you take?

We then passed the cards around so that each student passed cards 5 times, essentially making their card anonymous. They could then say their own comment or their card’s comment.

In the 60-student class it became quickly apparent I was being ‘trolled’ by the comments the students were choosing to share, which made the conversation fairly negative. It started as comments about the EU delegation refusing to negotiate, and then quickly turned to quoting the Trump administration’s position on the Paris Agreement (which would have been a good teachable moment, but I admittedly was flustered), followed by comments about how time could have been better spent reviewing for their final. Classes have their own energy, and that section had moments of general antagonism throughout the semester, though usually minor, so I should have been better prepared. I think with practice this portion could be engaging and useful, but it requires the facilitator to be ready to handle a variety of comments and to reposition the comments quickly. While I like having the activity come at the end of the semester, it does lend to a stressed student body.

The other, smaller, class had a much more genuine response. I expect a big portion of their genuine response was because of a statement from an international student prior to the card writing. She described how the activity had been gratifying, having been in the country during the Obama administration and seeing the change to today’s administration. She described the tone of the American diplomacy abroad these days, and described it in reference to the US position in the game we’d just played. That class was also more good-natured in general. They brought up empathy, and how they learned about needing to peak emissions early, for example.

Student response cards:

  • I don’t know what actions I could take.
  • I think the world is screwed.
  • I feel kind of scared with how our countries are handling climate change.
  • 1. We need to get our sh*t together. 2. Scared for our future. 3. Be more conscious.
  • How do you feel? Absolutely exhausted.
  • I learned that no matter how much we try the world is screwed because of climate change.
  • 1. From this I learned that this world is dying. I don’t like how sh*tty it is. 2. Sh*tty about how many people may or may not die.

37% of the cards were what I categorized as nihilistic or frightened. This is, frankly, not an unexpected response to an activity like this. I spent a lot of time talking about impacts in order to impress upon them the importance of engaging with this activity. Some of the folks in this group however, saw that this was a problem and said “It will take a lot more money to fix these climate problems. Not worth the money.” They also stated that they felt “Fantastic”. While that was one particular student, one might expect that statement from a more conservative audience. I attempted, in the moment, to describe the economics of climate change as a loan we take out that our children have to pay back with considerable interest, I’m not sure that analogy really stuck.

Some of these cards are also a peak into a group of students who are interested in the issue, however do not know what to do. While we talked about various responses to modern climate change, I am very wary of appearing like I’m advocating for a particular action. Many of the cards state the students are unsure of actions they individually can take, or that individual actions are ineffective. This is a particular point that I will try to address in the future, to describe the nature of climate as a collective action problem requiring that individuals, yes, do their part, but that the onus of action needs to be on governments to enact and enforce legislation.

What did you learn:

  • I learned how important these issues actually are. Our world is strongly impacted and if there is no change we will be drastically hit with consequences. How do you feel: Lost for words at the fact that the US is truly hated. What will you do: I will try to take part in the change.
  • I learned about the view of points of an outside nation towards the US, this experience gave me a chance to look from the outside in. I also have a better understanding of world climate, and how to go about finding a solution. I will continue to find ways to go green and continue recycling and not litter.
  • 1. That several nations really can’t help as much simply due to the amount of poverty in their nation. 2. That it will take more open minded plans to actually make a serious difference. 3. I will try to keep my mind open to interpretation of how other countries function and operate.
  • I learned that the developing nations make a big difference with their changes. I feel frustrated and disappointed. I will talk more about the issue. Look for petitions folks.
  • I learned that getting all of the countries to come together is damn near impossible. We don’t care about each other enough. We need to see the bigger picture that is all of us as a whole. Be the change you want to see in the world. Live as green as possible.
  • I feel if we [are] to really understand each other and realize we need to have the same goal to better our world, we would come together.
  • I learned that if we don’t start making changes right now, developing countries will be at risk. I feel motivated to make changes. I will try to reduce my CO2 emissions and advise others to do the same.
  • I feel so small.

The last group is the most optimistic. While there is considerable anger expressed by the group, they wrote about the need for a group solution, and expressed frustration that it was so difficult for people to actually ‘care about each other enough.’ These are the folks that want to accomplish something to positively effect their lives. It’s roughly a third of the class. Given the pre-class surveys that I gave them at the beginning of the semester, there’s considerable movement on student interest in climate change and their desire to engage with solutions.

Advice for employing this game:

Make sure you have something to have a positive action they can take with their new desire to fix the climate. I have not solved that problem given the classroom setting, but I hope to by this time next semester.

10 students in each group is probably as large as I’d go with students. I know there are modifications for large groups in the facilitator guide, so check there if you have large sections. I think having a larger “Other Developing Countries” block and forcing them to negotiate within themselves before bringing their position to the UN would be fascinating, but too complicated.

Build a case for optimism. I had a lot of students walk out of that room without hope. That’s counter productive, when the goal of the activity is to give them an understanding of the scope, a feeling that they’re in this with lots of others, and then a guiding hand in what they can to do help in their way.

Inequity is key. While it may seem like a small detail, making the developing countries uncomfortable, and the US/EU feel like royalty adds tension.

The first round requires a decent amount of learning on the fly. While both sections caught on quickly, 5-10 minutes of additional time in that first negotiating round is very useful.

Be prepared for an adversarial comment within the ‘debrief’ period if this is an in-class activity. While the vast majority of the comments that I looked through were supportive of the activity, there are several that think it was a waste of time. Such is the nature of having 90 students engage in a, sadly, politically controversial game.

The main advise I have, however, is to do this. It is a phenomenal way to engage a class in learning about their world, and what is happening to it.

Dr. Heather L. Ford, Paleoclimatologist

Dr. Ford sampling marine sediment that was brought up from the bottom of the seafloor.

What do you do as a geoscientist?

I’m a climate scientist interested in past archives of climate change. I explore warm climates of the past to help understand future climate change. I look at the ocean’s role in moving around heat and carbon in the earth’s system.

What is your data, and how do you obtain it?

I work on marine sediment from the bottom of the ocean. Within this sediment are tiny fossil shells, the size of a single grain of sand. The chemistry of these fossil shells, formed by protists called foraminifera, can be used to reconstruct temperature, ice volume, carbon chemistry, and many other properties of the ocean. In the laboratory, I chemically clean these shells to remove contaminants and analyze them by mass spectrometry. Using the minor and trace elements of these shells I’m able to reconstruct climate conditions from a warm period approximately three million years ago, the Pliocene warm period, when atmospheric carbon dioxide levels are estimated to be similar to today with human inputs.

How does your research contribute to the understanding of climate change?

My research contributes to our understanding of climate change by understanding the most recent period of sustained warmth. One focus of my research is to understand the tropical Pacific Ocean through time and how it influences global climate. The importance of the tropical Pacific is exemplified by the ocean-atmospheric changes during an El Niño-Southern Oscillation (ENSO) event which alters global climate. Today, the tropical Pacific is characterized by a western warm pool and an eastern cold tongue. The thermocline, the uppermost layer of the ocean within which temperature decreases rapidly with depth, plays a critical role in this tropical Pacific temperature pattern and ENSO development. During the warm Pliocene, records show the eastern tropical Pacific was warmer than today. My research shows the thermocline was deep which contributed to the warm temperatures in the eastern tropical Pacific. This altered tropical ocean-atmosphere dynamics which we call El Padre (figure below).

What is your favorite part about being a scientist?

I’ve cultivated a group of phenomenal collaborators that I enjoy working with. We ask questions that are relevant to future climate change and are inspired by each other’s dedication.

What advice do you have for aspiring scientists?

Take a programing class! I started coding in graduate school and although I am by no means a master coder, I’ve been able to explore datasets and examine relationships in climate data.

To learn more about Heather’s research, you can follow on her on Twitter here or visit her website

Witnessing a Murder: Snorkeling the Great Barrier Reef

Adriane here-

A view of Queensland and its coastline in northeastern Australia (inset image). The Great Barrier Reef is the long feature, highlighted by the white lines, that stretches along the coast. Images from Google Earth (2017).

Last summer, I was lucky enough to be chosen as one of the scientists to sail on the International Ocean Discovery Program Expedition 371 to the Tasman Sea (read more about my adventure here). The ship we sailed on, the JOIDES Resolution, left from the port of Townsville, Australia. Because I was already flying to the Southern Hemisphere, my husband and I decided it was the perfect opportunity to take our delayed honeymoon (we had been married two years at that point, but better late than never!). We stayed on Magnetic Island, located right offshore from the city of Townsville for a week, sight seeing, koala-petting (Queensland is one of the few places in the world that allows you to pet wild koalas), and snorkeling.

A rare sight: An on-the-move koala family on Magnetic Island.

Being a naturalist and animal-lover, I have quite a lengthy bucket list. One of the items on that list was to snorkel the Great Barrier Reef. Lucky for me, the reef was just a 2 hour boat ride from Magnetic Island! My husband and I signed up months in advance for a snorkeling adventure on the reef, and we were both extremely excited about it! I prepared for the snorkeling adventure by doing extensive research on the reef, learning species of corals, fish, and sharks that are common on the reef, and also what human-made products (such as sunscreen) were harmful to the reef so we could avoid using them the day of our snorkel. But I also had to prepare myself mentally for what I knew was unavoidable: witnessing a reef community in peril.

Lodestone Reef, a small reef part of the Great Barrier Reef that we snorkeled.

Before I explain, allow me to dazzle you with reef facts. Reefs all over the world are amazing places (OK, this is probably more of an opinion, but I’m not wrong, right?). They are home to a huge number of animal species, all who interact with each other. Reefs themselves are defined by the community of corals, fish, crabs, etc. that live together. Reefs are located in warm, shallow, clear waters, and that is why they are found in tropical waters. Reefs occur all across the world, but the biggest and most impressive reef, by far, is the Great Barrier Reef. Check out this Google Street View of Heron Island, Great Barrier Reef to see some of the wildlife and coral species that live on the reef.

A colony of healthy table coral with striped damselfish swimming about.

The Great Barrier Reef (I’ll refer to it as the GBR from here) stretches 2,300 kilometers (1,430 miles) along the Queensland (northeastern Australia) coastline. It covers about 344,400 square kilometers (132,974 square miles) of area, which is approximately the size of 70 million football fields, or the size of Italy. Because of its size, the GBR is visible from space, and is listed as one of the 7 wonders of the world. Together, the GBR is made up of 2,900 individual reefs, and contains 600 continental islands. It also includes about 300 coral cays (cays, or keys, are small sandy areas located near a coral reef) and ~150 mangrove islands (mangroves are an important plant that live along coastlines; their roots offer protection for small fish and animals and help stabilize the soil in which they grow).

The reef itself is home to over 1,625 fish species, which accounts for ~10% of the world’s fish species! The fish rely on over 600 species of corals for protection and shelter. Over 133 species of sharks and rays also inhabit the reef, feeding off fish. Sea snakes slither their way across the reef, with about 14 different species found in the GBR. 30 species of whales and dolphins also visit the warm, clear waters of the reef to raise their young every year. Of the 7 species of marine turtles alive today, 6 can be found in the GBR. Thus, the GBR is a true natural treasure, with its beautiful marine life, vibrantly colored corals, and abundance of geographic features.

A solitary (one animal that lived by itself rather than in a colony) horn coral, one of the earliest species of corals from the Ordovician. Image from the Digital Atlas of Ordovician Life.

Corals first appeared in the rock record ~548 million years ago during the Cambrian Period. True reefs didn’t make an appearance until about 100 million years later, during the Ordovician Period. These reefs were very different from our reefs today, but the point is, they have survived all 5 major mass extinctions  in Earth’s history, and have become extremely successful. But all of that is changing today with global climate change. Reefs all over the world are in dying because of us, humans. It is estimated that from 1985-2012, about 50% of the GBR corals have died (De’ath et al., 2012).

Global climate change caused by humans expelling carbon dioxide (CO2), a greenhouse gas, at an accelerated rate is the leading cause of coral reef decline. As our atmosphere warms, our oceans are also warming. The oceans absorb about 93% of atmospheric heat. Although corals thrive in warm waters, they have a very narrow temperature tolerance (most can live in waters no less than 64 degrees Fahrenheit, and no more than 84 degrees Fahrenheit). When waters become too warm for the corals, they become extremely stressed. Prolonged stress leads to coral bleaching events. This occurs when corals expel the algae, called zooxanthellae, that live in their tissue. The zooxanthellae are what give corals their colors, so after expulsion, the coral turns white. Corals can survive without their zooxanthellae for a short period of time, but if they don’t return, the coral then dies. Check out this page and graphic by NOAA to understand more about coral bleaching.

My husband swimming next to a healthy community of various coral species. Some of the corals at Lodestone Reef are enormous, which indicates the coral is probably decades old.

Coral skeletons are made of calcium carbonate, or calcite (CaCO3). This mineral is also what bivalves and gastropods make their shells out of, so it is commonly found in reef environments. As humans pump more CO2 into the atmosphere, the oceans not only absorb heat, they also absorb this CO2 (about 30% of the CO2 released by humans has been absorbed by our oceans).  When CO2 is dissolved in seawater, it creates biocarbonate ions, carbonate ions, free hydrogen ions, and carbonic acid (read more about this process on our ‘Ocean Chemistry & Acidification‘ page). The amount of free hydrogen ions, H+, are what causes ocean waters to become more acidic or basic. An increase in H+ ions leads to the ocean becoming acidic, whereas a decrease in H+ ions leads to more basic waters. So as the oceans absorb more CO2, they become more acidic. Calcium carbonate, what corals make their skeletons out of, dissolve in the presence of acid. So not only are the corals stressed from increased water temperatures, it is also harder for them to grow and build colonies because they are dissolving in increasingly acidic waters.

Elkhorn corals in various stages of bleaching at Lodestone Reef. The fleshy-colored coral at the top of the image is healthy, the white coral directly under it is bleached, and the dark coral with bacteria feeding off the dead animal is at the bottom of the image.

I was well aware of the effects of global climate change on reef communities before I snorkeled the GBR (at this time, one of the worse coral bleaching events was taking place), but I had never seen the effects of human life on the reefs up close and personal. When we jumped off the boat (which was aptly named ‘Adrenaline’) at Lodestone Reef, I was instantly blown away by the wildlife swimming all around me. Sea cucumbers, starfish, and fish were everywhere, as were several species of coral! Elkhorn coral, brain coral, and species of table coral were abundant all around us. I was in total and absolute awe.

But it didn’t take long to find stressed, dying, and dead corals. Healthy corals are vibrantly colored, while some are flesh-colored. Stressed corals experiencing bleaching events are white, and those that are dead appear black. Dead corals will also have wispy bacteria hanging off the skeletons, as they are feeding off the decaying flesh of the animal. My heart sank faster than an anchor thrown overboard when I first witnessed the stressed, dying, and dead corals. Here I was, in the midst of the world’s largest, most wondrous reef, and it was being decimated. Suddenly, I was overcome with guilt: Guilt at not living a more earth-friendly lifestyle, guilt at not talking about the effects of climate change and its effects on reefs more to my students and the public, guilt that humans are carelessly destroying our Earth’s most precious resources. I was, in fact, witness to one of the largest, most extensive mass murders taking place in my lifetime: the death of our coral reefs.

But I’m not one to end on a sad note; rather, I’m hopeful that we can help our reefs (and all marine life) rebound from the damages we have incurred. There are several organizations that are committed to protecting the Great Barrier Reef and reefs all around the world. Some countries have created fishing restrictions and regulations for their reefs to protect the fish and marine communities that inhabit them. The Paris Agreement, a coalition of over 195 countries, was created in 2015 to  curb global CO2 emissions (as of writing this post, the U.S. is still a member of the agreement, but has plans to withdraw by November 2020). Scientists are gathering data on our reefs to quantify how fast they are responding to climate change, and are also working with aquariums to regrow species of corals for release back into the wild. As an individual, you can contribute to protecting our reefs in quite a few ways. First, you can actively vote for government officials that have a track record in supporting science and curbing CO2 emissions. Second, recycle. Most of our trash ends up in the oceans, and that leads to another set of problems for marine life. Third, you can reduce the amount of plastics you use in your daily life by refusing straws at restaurants, using reusable bags, baggies, and containers. Fourth, reduce the amount of time you spend driving a car. Instead, take public transportation, ride a bike, walk, or carpool with friends and family. All of these activities reduce your carbon footprint. Lastly, you can donate to foundations and organizations that work to protect our reefs. 

Here’s a list of foundations and organizations that are committed to protecting our reefs, and places where you can find additional information about reefs:




Intergovernmental Panel on Climate Change (IPCC) I: Current Climate-Driven Impacts

Andy here –

Teaching about climate change this year took a toll on me. I’m normally a resilient and fairly hopeful person, but diving into the current and future impacts of climate change commonly leaves a person shell-shocked. How do climate scientists cope with existential dread?

Scientists are people too. Some of us are young, many of us have kids. It is difficult to stare this problem in the face day in and day out, without feeling like you are watching a slow motion train wreck, with your elected officials stepping on the gas rather than using the brakes. I’ve decided that I’m going to share those feelings with other people. We’re starting with the current impacts. A second post will follow with the basics of climate modeling, and finishing with what we think will happen next.

What follows here is a small, incomplete collection of current climate-driven impacts and assorted links to other information. I’ve tried to keep it to just impacts that are established in the Intergovernmental Panel on Climate Change (IPCC). These are things that science can firmly establish as happening right now due to climate change.

Hydrological (Water) Cycle

Data showing percent of days per year with much below normal rainfall amounts (brown bars) and much above normal rainfall (green bars) within the continuous U.S. Notice that as you move from 1910 to 2010, the length of the brown bars decreases, while the length of the green bars increases. This indicates that there has been increasingly more days with rainfall. Data from NOAA U.S. Climate Extremes Index (CIE).

We can currently say there are substantial changes to where and how rain and snow fall because of climate change. These changes have altered our ability to use water, both in quantity and quality. If we look at Michigan as an example, it has an increase in yearly precipitation of 2/3 of an inch per decade since 1960. Massachusetts has seen >1 inch per decade (data here). Other states are not as lucky, and are currently seeing a decrease (e.g., California). Our freshwater is increasingly contaminated due to both low (drought) and high (flood) conditions in many locations in the US. 10% of counties are currently under high or extreme risk of a water shortage.

We, as humans, are at the start of these changes as well.

If you’re curious what the US government has to say about water use changes, click here for the National Climate Assessment Water Use (from 2014) page. It also has very scary maps!

IPCC: In many regions, changing precipitation or melting snow and ice are altering hydrological systems, affecting water resources in terms of quantity and quality (medium confidence).

Click here to explore the National Climate Assessment site’s findings from 2014 on water supplies.


We can also say that animals, plants, and other organisms have had responses to climate change. Coral reefs are the easy and moderately better-known connection, what with nearly 50% of the Great Barrier Reef corals dead in the northern section. Polar bears are similarly simple. With the arctic warming faster than the globe, 3/19 tracked polar bear populations are shrinking, while we don’t have enough data to say anything about the other 9/19. At least one of the ‘stable’ populations has shrunk since 25 years ago (stability is a ~12 year average). More warm winters mean more ticks in moose territory. A warmer West coast means stressed salmon. And so on.

While a projection (estimation based on current data), which I’m trying to save until later, click here for a map visualizing how species will need to move to maintain their proper habitat in a climate-shifting world.

IPCC: Many terrestrial, freshwater, and marine species have shifted their geographic ranges, seasonal activities, migration patterns, abundances, and species interactions in response to ongoing climate change (high confidence).


Climate change also has a negative effect on crop growth. Unlike what Lamar Smith has written (R-TX, head of the House Committee on Science, Space, and Technology), we do not expect there to be a benefit of increased CO2 in plant growth. Temperature effects far outweigh the small growth boost of higher CO2, and will lead to decreased seed yields. Climate change will shift where things grow; in some areas of India that used to get more snow there are new potato crops growing now with the milder winters. That’s good, but it’s quite the outlier. Wheat, rice, maize, soybean, barley and sorghum all respond negatively in rising temperature. Wheat production has already dropped 5.5%, and Maize by 3.8%. That is with our limited (in the face of what is projected) temperature changes so far.

Click here for an article by Scott Johnson that goes into more detail.

IPCC: Based on many studies covering a wide range of regions and crops, negative impacts of climate change on crop yields have been more common than positive impacts (high confidence).

Graph of projected increases (cool colors) and decreases (warm colors) of crop yields in the coming decades under increased warming. Notice how decreasing crop yields are more prevalent from 2010-2029 to 2090-2109. Image from IPCC (2014).

Extreme Weather Events

A) Percent of summer days when maximum temperatures exceeded long-term daily 95th percentile (the hottest recorded temperatures) from 1880 to 2005 over Western Europe. B) Heat wave intensity (number of days heat waves lasted) in Western Europe. Data from the Norwegian Meteorological Institute, 2013.

Climate change also increases the chances of having extreme weather events. Importantly, we can’t say that an individual hurricane is directly a result of climate change. We can say, however, that they are more likely. We can say that they’re made stronger, when they do happen. Harvey and others aren’t because of climate change but they’re more likely to happen and be worse because of it. Storms like Harvey, or Maria, or Irma, or Ophelia (which even hit the UK!) are more likely, and therefore more frequent, because of our warmer world.

Wildfires (click here for more details) are also made more common, due to drier conditions in some areas. So are floods, where there’s an increase in precipitation. And heatwaves. And on, and on.

This will obviously stress our systems to care for those affected. Given this summer and fall, I shouldn’t really need to back up that claim with supporting data.

IPCC: Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability (very high confidence).

Economic Impacts

Climate change has cost us money, and it will likely continue to cost us. We can say this with a high degree of certainty. Wildfires, floods, storms, droughts, earthquakes, tsunamis, all have a monetary cost. The insurance industry is well aware of the increasing trend in the costs, and so keeps track. We can divide the cost of these natural disasters into things that will be altered by climate change (wildfires, floods, storms, droughts, so on) and those not affected by climate change (earthquakes, tsunamis, etc.). This acts as a nice check against our buildings being more expensive, disaster relief being more expensive, or something like that. When we do this, all of the climate-related costs are increasing dramatically (click here for more details), while those not affected by climate change are only increasingly slightly. The number of climate-related (or extreme-weather) disasters is increasing, while the number of earthquakes is flat.

IPCC: Direct and insured losses from weather-related disasters have increased substantially in recent decades, both globally and regionally.

Ocean Temperature Changes

Top: Observed global annual averaged land and ocean surface temperature anomalies. Bottom: Same data as above, but decadal averages. Grey boxes represent uncertainty. Image from IPCC (2014).

Many of the ocean acidification impacts are similar or work alongside the impacts of increases in ocean temperature (click here for more details). Two examples: Corals bleach primarily due to temperature and their ‘skeletons’ fall apart in response to the pH. Similarly, when temperature rises, krill reproduce in smaller numbers. Krill are a key part of the food chain for things that people find cute, like penguins, seals, and many whales. Together, if those larger animals are stressed or starve, their predators die too.

Warmer water also expands, so a warmer ocean means that sea-level rise occurs more as well. This can magnify the storm surges, amplifies the effect of the melting glacial waters, and is generally a very bad thing.

Oh yeah, and the rate that the ocean is warming is accelerating.

Ocean Acidification

Many things have changed in the oceans due to the increase in carbon dioxide in the atmosphere. The first is that the ocean has absorbed quite a bit of that carbon dioxide. The pH has changed by 0.1 units since the industrial revolution. pH scales are not linear, so this actually is a 30% increase in acidity.

Marine life obviously feels this massive change. Because they are smaller and more fragile, larval stages of various organisms or plankton feel the effects first. While there are other things at issue (though research is working on detangling the others: water quality issues, low oxygen, or changes in diseases, etc.), the current rash of losses in the oyster industry are at least partially due to changes in acidity. The oyster industry is a $100-million-a-year industry. Click here for more details.

Corals, too, are stressed. Coral bleaching is due to temperature, but the material that corals make their skeletons out of is susceptible to acidification. It makes it harder for them to reproduce, grow, and live. They also dissolve and erode faster under higher amounts of acid.

There are currently more than a million other species living in coral reefs, making reefs some of the greatest spots of diversity on Earth.

Sea Level Rise

Top: Average sea ice extent in millions of km squared for the Arctic and Antarctica from 1900 to 2010. The Arctic is melting at an alarming rate. Bottom: Global average sea level rise in meters from 1900 to 2010. Image from IPCC (2014).

Sea level has risen between 10-25 centimeters. Because much of the coast is really flat, that means much more area has been lost than it appears. We think that the loss to property values is between $3-5 billion a year. In structural loss, it is $500 million. We spend a lot of money to keep the coast where it is too; like the $14 billion Louisiana is expecting to put into coastal barriers along the Mississippi River delta. In other areas, the coast just erodes and land disappears into the ocean. Click here for more details.

Click here for a neat NOAA page that lets you see what happens as sea level rises.

We know sea level rise also has a cost on communities and lives. An entire community, Shishmaref in Alaska, has lost 2,500 to 3,000 feet of land in 35 years. Other communities, Kivalina, Newtok, Shaktoolik, and others (31 in total) need to be moved according to the Army Corps of Engineers. At least one community has voted to move to the mainland, but without funding to move, cannot.

Marginalized Communities

Climate change is a volume knob for social justice issues. That volume knob is sensitive.

Communities that are marginalized (have less political power, less money, etc.) are far more at risk in a changing world. If you have less power in society, odds are that a society under stress from climate change will be less likely to support you in the face of needs (even a lesser need) of a more powerful,other group.

This is referred to as ‘Climate Justice’. The People’s Climate March in Washington, D.C. (2017) was a wonderful example of how this has been embraced. From what I could tell, there were far more people there interested in social justice (indigenous communities, religious communities, etc.) than the scientists or folks who allied themselves with science at the march. It’s called the People’s Climate March for a reason. Click here for the NAACP’s page on Climate and Environmental Justice.

There is no clearer example than what happened and is currently happening in the US in 2017. Puerto Rico is not a state. Florida and Texas are. The US response to Puerto Rico which, again, is a part of the United States of America is the textbook example of this. Puerto Rico does not have representation in the federal government, so is ‘less important’ from a hardline (and inhumane) political point of view. The differing response from the federal government is a direct and obvious example of this IPCC finding.

Click here for more details on climate justice.

IPCC: Differences in vulnerability and exposure arise from non-climatic factors and from multidimensional inequalities often produced by uneven development processes (very high confidence). These differences shape differential risks from climate change.


Climate change is currently changing the water cycle, changing how water resources can be accessed. We’ve seen that animals and plants are already shifting their habitats due to climate change. A specific, but very human-centric part of that is how crops are and will respond. Harvests, in bulk, are down for many of our grains. Climate change has already cost us lots of money, and will continue to.

Lastly, but probably most importantly, climate change is currently felt by disadvantaged peoples disproportionately. The US response to Puerto Rico which is a part of the US is the textbook example of this. Puerto Rico does not have statehood, so is ‘less important’ from a hardline (and inhumane) political point of view.

We cannot, scientifically, say that Maria and Harvey and Irma and Ophelia are because of climate change. Attribution is difficult due to the statistics involved. We can however say that the scientific prediction for what happens in a warmer world is larger, more damaging and frequent storms. That is what we experienced in 2017.


IPCC, 2014. Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II, and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (Core Writing Team, R.K. Pachauri and L.A. Meyer, eds.). IPCC, Geneva, Switzerland, 151 pp.

‘Extreme Climate Events in Europe: preparing for climate change adaptation”, 2013. Norwegian Meteorlogical Institute, Oslow, Norway, 140 pp. 

Darwin Day Celebrations 2018

Maggie here –

The Darwin Day events at the University of Tennessee, Knoxville have been running since 1997 and I was one of the leaders for the 2018 events. Darwin Day is all about celebrating the life and work of Charles Darwin, and sharing that information with members of the UT campus as well as the surrounding community in Knoxville. For this year’s celebration we hosted a birthday party in collaboration with a McClung Museum Family Fun Day and had a special keynote lecture by Dr. Nizar Ibrahim.

Darwin and Wallace puppets that are used to advertise our Darwin Day events. These puppets are ~10 feet tall and our very wonderful friends wear them and walk around or even dance in them!

The birthday party had cake (of course!), games, crafts, a scavenger hunt, and a larger-than-life puppet of Charles Darwin. This year, we wanted to make sure that our activities were designed to be able to really teach about evolution. One of the activities was to test out different “finch beaks” to see how easy it was to pick up “food”. Our finch beaks consisted of paper clips, binder clips, and wooden skewers that were used to pick up different objects. For our younger guests this activity concluded with a quick talk about which beak they thought was easier to use and how that might translate to real beaks on birds. For our older guests we were able to bring in the ideas of adaptations, natural selection, and speciation during the wrap up conversation. We were also lucky enough to have one of the McClung Museum docents come in for the birthday party to lead a couple of tours through the Human Origins exhibit. This was the first time that these tours had been led during Darwin’s Birthday party and helped us engage in evolution discussions with our older guests. As with any large scale event, each year is a little different and we continually try to come up with new activities and try to reach new areas of the Knoxville community. While this birthday party was incredibly successful (we had ~260 people come!) we are already looking forward to next year and making the birthday party even more successful!

Leslie Chang Jantz, Curator of Education; Callie Bennet, Asst. Museum Educator; Emily Nield, Earth and Planetary Sciences graduate student all work to pass out cake and snacks to birthday party guests.

The evening lecture with Dr. Ibrahim was a rewarding excursion through the past. He has done significant work reconstructing the ecosystems of the Cretaceous of Morocco. He has primarily worked on uncovering an ancient river system community that was dominated by many types of predatory animals, namely Spinosaurus. There was a special underlying story on a German paleontologist, Ernst Stromer, who originally discovered Spinosaurus, but the specimens were lost during World War II in the bombing of Munich. Dr. Ibrahim was able to find another specimen of Spinosaurus in Morocco -his “needle in the Sahara”. He worked with local fossil hunters as well as a museum in Italy and was able to find more bones that belonged to Spinosaurus. There is not yet a complete skeleton of Spinosaurus.  However, with new technology researchers were able to 3D print the skeleton of Spinosaurus that tours museums today. Dr. Ibrahim’s talk impressed upon the audience that paleontology is hard work, but that collaboration with other scientists and foundations can ease that burden and make discoveries that much more rewarding. He also gave great insight on the challenges that come with doing field work in the Sahara desert and how terrifying it can be when two of your three vehicles break down in the middle of the desert! I think I’ll stick to local field work and museums…

Artists rendition of Spinosaurus in the Cretaceous river system of Morocco. Painting by Davide Bonadonna.

Putting on a large scale event like Darwin Day during the last year of my Master’s degree was very challenging-I often felt that if my days weren’t planned well or if I wasn’t working a month ahead of schedule that I wouldn’t be able to pull off writing my thesis and planning a birthday party and speaker visit! It was incredibly difficult, but doing outreach events like this are what makes science rewarding in my eyes. I have spent several years cultivating my scientific knowledge, but my passion (outside of research!) is doing outreach and talking to the communities that I work and live in about science and sharing my excitement about research with them. Darwin Day at UT changes and morphs every year based on who is leading it, but it continues to grow and continues to reach more people as the focus becomes more centered on reaching the communities surrounding the university. I also have to thank Jen Bauer, Joy Buongiorno, and Audrey Martin, as well as all of the other volunteers, for their help and support with executing this year’s Darwin Day events-these events could not have happened without the help of other amazing scientists who want to share science with the public!

Click here for an interview that discussses the Darwin Day program at UT.

Ranjeev Epa, Invertebrate Paleontologist

Fig. 1: End to an intense day of fossil collecting

I am an invertebrate paleontologist. My research interests are mainly focused on paleoecological themes, especially investigating biotic interactions (predator-prey relationships, paleoparasitism) and exploring how variations in body morphology (the form of living things) can be used as a proxy to interpret paleoenvironmental attributes. As an example, in snails, shell shapes and ornamentation (ex. spines or other shell modifications) can be influenced by predators (biotic) and/or by abiotic factors, like flow rate or nature of the substrate (the sediment or rock on which the animal lives).

I work primarily on marine invertebrates. My favorites include gastropods (snails), bivalves (clams), elephant tusk snails (which are very cool), sea urchins, and foraminfera. I started my journey in my home country, Sri Lanka, where I worked on Miocene marine fossils of Aruwakkalu in Sri Lanka (Epa et al., 2011). After joining Ohio University for my masters, I studied the late Oligocene freshwater ampullariid snails of Tanzania (Epa et al., 2017 in press). Currently, I am investigating predatory and parasitic interactions within a collection of Plio-Pleistocene marine bivalves from Florida. Here, I look at predatory drill holes (Fig.2C) and trematode (a group of flatworms) parasitic traces (blisters and pits; see Fig.2A and B) to explore taxonomic selectivities (specific animals getting harmed) and to investigate potential relationships between environmental factors and variability in intensity of such biotic interactions.

Fig 2. A – B: Potential traces of trematode parasitism. A. Pits. B. Blisters.
C. Oichnus paraboloides Bromley, 1981, predatory drill hole produced by a naticid gastropod

Bivalves (clams) are not only pretty (Fig.3) but also one of the key contributors in maintaining good ecosystem health, thus acting as keystone species at local geographic scales. In addition, throughout human history, bivalves (mollusks  in general) have been an important component in the food industry and many communities around the world have direct interactions/dependence on their regional mollusc communities (malacofauna).  Thus, community structure and population dynamics of bivalves affect ecosystem health, human health and, to a large extent, economies of coastal communities.

One of the research questions I address in my doctoral research is the effects and factors governing trematode parasitism among bivalves. Parasitism is known to cause detrimental effects on bivalves. However, little work has been done on paleoparasitology compared with other biotic interactions like predation. So, my research will look in to the geological and modern records/trends of trematode parasitism in bivalves to explore factors that influence variation in parasitism. Using these data, I plan to interpret how climate change can influence parasitism among bivalves and add a novel dimension to stress the importance of reducing our footprint on Earth.

Fig 3. Pectens collected from Sri Lanka

There is so much I love about what I am doing. Getting to work with my favorite animals makes me feel that I have the best job in the world. As a scientist, you have the power to communicate important scientific findings to people with different academic backgrounds and to people that hold different societal positions. This is especially important as at present, as our carbon footprint on the blue planet is a serious cause for concern. My advice to young scientists is simple: love what you do and do what you love. ALWAYS try to maintain a balance in life.

Follow Ranjeev’s research profile by clicking here and keep up with his updates on Twitter here.

New echinoderm fossils from Anticosti Island, Quebec

Late Ordovician (Hirnantian) diploporitan fauna of Anticosti Island, Quebec, Canada: implications for evolutionary and biogeographic patterns

Sarah L. Sheffield, William I. Ausich, Colin D. Sumrall

What data [were] used? New fossils found from Anticosti Island in Quebec, Canada.

Methods: New fossils of poorly understood echinoderm (relatives of sea stars) fossils discovered from Upper Ordovician (445-443 million years ago) rocks were analyzed and compared with middle Silurian (434-428 million years ago) to better understand biogeographic and evolutionary trends.

Results: The Holocystites Fauna is a group of poorly-understood diploporitan echinoderms (a term that just means they breathe out of sets of double pores found on their body) that scientists assumed to have only lived in the midcontinent of the United States (e.g., Tennessee, Iowa, Indiana, etc.) during a very specific time within the Silurian. New fossil species Holocystites salmoensis, however, tells us that they actually also lived during the Late Ordovician of Canada, which extends their known range nearly 10-15 million years!

This fossil of Holocystites salmoensis represents a very important new datapoint that helps scientists understand poorly known echinoderm transitions from the Late Ordovician to the Silurian. A. The mouth area of Holocystites salmoensis. B. a close up of the diplopore respiratory structures. C. A line drawing of the mouth area of Holocystites salmoensis. D-E. Other fossils of Holocystites salmoensis and (F) an unidentified diploporitan found in the same deposit (Sheffield et al., 2017).

Why is this study important? So at first glance, this paper might not seem so important-it’s just one new fossil of a relatively rare group of echinoderms. What is so important about this is the time in which these fossils were found. Rocks from the Upper Ordovician, during which this fossil was found, are very rare because the ocean levels were very low. Earth was in an ice age, so a lot of ocean water was taken up in glacial ice. When sea levels are low, fewer rocks are preserved; therefore, fossil data from low sea levels are rare. Evolutionary transitions of fossils from the Ordovician through the Silurian aren’t well understood. Now that we’ve found evidence of Ordovician Holocystites, we can infer a lot more about when and how these organisms evolved.

The big picture: Crucial information about how life on Earth evolved is often hard to find from times like the Late Ordovician. Actively searching for rocks during these times and identiying fossils from within them can tell us a lot about how past life responded to mass climate change (like ice ages and significant warming periods). It can also tell us a lot about how organisms expanded and shrunk their biogeographic range. Even one new fossil, like the one identified in this paper, can change a lot about what we think we knew!

Citation: Sheffield, S.L., Ausich, W.I., Sumrall, C.D., 2017. Late Ordovician (Hirnantian) diploporitan fauna of Anticosti Island, Quebec, Canada: implications for evolutionary and biogeographic patterns: Journal of Canadian Earth Sciences, v. 55, p. 1-7, doi: 10.1139/cjes-2017-0160

On when you don’t uncover a clear answer

Sarah here –

Last summer, I went to southern Indiana to do some fieldwork with my undergraduate research student, the wonderful and intelligent Sarah Johnson (who has since graduated and gotten an excellent job working at an environmental consulting firm in Texas). We went there to collect data to answer a really intriguing question that, I am very sorry to report here, we still do not have an answer to. This post is about fieldwork, undergraduate research, and even more importantly, the importance of reporting the experiments and the field expeditions that just didn’t work out.

I work on a group of unusual extinct echinoderms, the diploporitans (you can read more about them here). One of the many weird things about this group of echinoderms is that no one can find fossil evidence of them as juveniles- we only find them as adults. All living echinoderms have a free-swimming larval stage- meaning, even the echinoderms that don’t move much as adults (like crinoids) are quite mobile as juveniles! For other groups of fossil echinoderms (like blastoids), there are plenty of examples of very small juveniles that likely moved the way that modern ones do-as larvae. However, there’s no known fossil evidence for this in the diploporitans.

This is a specimen of an adult diploporitan, found near Napoleon, Indiana. We spent a lot of time this past summer looking for juveniles, but unfortunately, didn’t find any.

So my student, Sarah, and I went to the one place in the United States that we would expect to find juveniles, if there are any to be found- Napoleon, Indiana. The reason that we would expect to find juveniles is that there are a very large number of preserved adults there-which makes it more likely that smaller ones would also be there (too small to see with your eyes). Sarah and I searched the outcrop for hours looking for the areas that had the highest density of fossils, collected about 50 lbs worth of sediment, and drove back to Knoxville, TN.

Sarah and Russell Godkin, my other undergraduate research student, then spent the rest of the summer sifting through the seemingly endless buckets of sediment that we brought back-they used microscopes and analyzed the smallest sediment grains for all fossils. They pulled out thousands of tiny corals, brachiopods, and pieces of crinoids. However, after countless hours, they didn’t find a single diploporitan juvenile-not. a. one.

Obviously, we were all quite disappointed-we really wanted to find these fossils (and Sarah and Russell were really tired of looking into microscopes-but I digress). There’s an important lesson in here, though- the LACK of an answer is just as important. The lack of an answer can help us develop new hypotheses as to why we can’t find these juveniles and it can help other scientists better understand related questions about echinoderms and fossil preservation. So-never fear, the hunt to figure out what juvenile diploporitans looked like is still on!