Climate change mitigation beyond agriculture: a review of food system opportunities and implications

Meredith T. Niles, Richie Ahuja, Todd Barker, Jimena Esquivel, Sophie Gutterman, Martin C. Heller, Nelson Mango, Diana Portner, Rex Raimond, Cristina Tirado, Sonja Vermeulen

Summarized by Taylor Dickson, who is a senior currently majoring in Environmental Science at Binghamton University. They are an environmentally conscious and dedicated student with a hunger for knowledge. Taylor plans on pursuing field experience prior to the continuation of their education. Outside of the realm of education, they enjoy immersing themselves in nature as well as participating in and appreciating the arts.

What data were used? The data utilized in this article are derived from other research articles and compounded to create a bigger picture encompassing all aspects of the food system. This article incorporates important information regarding areas beyond the direct scope of food production. Such areas included are transportation and refrigeration methods, which have greenhouse gas emission consequences.

Methods: Combining and integrating recent research and expanding the exploration of mitigation opportunities by reviewing the relevance and effectiveness of these opportunities in several areas throughout the food system including pre-production and post-production. This study goes below the surface issue to expose the root areas that need to be addressed to create a more sustainable food system.

Results: The results incorporate all aspects of the food system while considering agricultural climate change mitigation. Included in these results are aspects of food production many people may often forget about including the transportation and storage of the food produced. Certain foods have higher emissions associated with them due to the necessary storage required for these food products as well as the circumstances surrounding the growing and harvesting of such products.

Food loss is experienced at all levels of consumption within the food system, including the pre- and post-consumer levels. Annually, about one third of all food products produced on a global scale result in being wasted or lost throughout the production process. At the production level of the food system, a significant source of greenhouse gas emissions is related to the production of synthetic fertilizers used for agricultural practices. This information demonstrates how vast the scope is of the food system discussed.

Greenhouse gas emissions are significantly higher regarding diets rich in animal derived products. This article utilizes other works which provide information and insight that shifting toward a more plant based diet will be beneficial to the environment in lowering greenhouse gas emissions as well as leading to a decrease in human mortality rate accompanied with an increase in health benefits.

Generally, refrigeration is necessary for around half of all food produced. Lower income countries often lose crops at the production stage due to a lack of technologies related to refrigeration and drying methods. Inadequate drying technologies lead to the development of mold and eventual spoiling of food products such as grains. Almost one fifth of the energy utilized by the food system in the United States is from household refrigeration. Transportation related emissions can be reduced primarily by shifting to more efficient modes of transportation. With many food products requiring refrigeration throughout the transportation process, greenhouse gas emissions of refrigerated transportation can reach up to 140% when compared to the emissions associated with non-refrigerated transportation vehicles.

Why is this study important? This study brings together results from previous studies in a cohesive paper which encapsulates information from several areas within the food system. Incorporating the many aspects of the food system in this study provides the reader with a broader understanding of the depth of each component within the system. A single issue of agriculture is broken down into multiple specific and more manageable subcategories where mitigation strategies are indulged. This study goes a step further and provides possible outcomes to the proposed mitigations and discusses potential consequences of these mitigation strategies.

The bigger picture: Climate change is an inevitable universal issue that everyone will face at some point in their lives, and one that demands immediate attention and mitigation. This study exposes the underlying issues of the food system that are significant contributors to climate change. It draws attention to the root causes of greenhouse gas emissions within the food system. The food system is much more than agricultural production. It includes often overlooked aspects related to pre-production and post-production such as packaging, transportation, and storage of the food produced. Although these issues begin at the production level with corporations, consumers hold some power and have the ability to aid mitigation strategies in their success. Some opportunities for these consumers to participate in as described in this article are to adopt a more plant based diet, refraining from over consumption, and understanding that perfection is an illusion and food does not have to be pleasing to look at for it to be nutritious and serve its purpose.

Citation: Niles, M. T. et al. Climate change mitigation beyond agriculture: a review of food system opportunities and implications. Renewable Agriculture and Food Systems 33, 297–308 (2018).

Tackling Climate Change with Machine Learning 

David Rolnick, Priya L. Donti, Lynn H. Kaack, Kelly Kochanski, Alexandre Lacoste, Kris Sankaran, Andrew Slavin Ross, Nikola Milojevic-Dupont, Natasha Jaques, Anna Waldman-Brown, Alexandra Luccioni, Tegan Maharaj, Evan D. Sherwin, S. Karthik Mukkavilli, Konrad P. Kording, Carla Gomes, Andrew Y. Ng, Demis Hassabis, John C. Platt, Felix Creutzig, Jennifer Chayes, Yoshua Bengio

Summarized by Samir, a first year masters’ student at Binghamton University State University of New York majoring in geosciences. He has experiences in designing and delivering effective solutions using programming skills and knowledge in geosciences, physics, and mathematics. Also, he is planning to dive into machine learning since he believes it is one of the most effective methods to tackle global issues! By the way, he is a big fan of basketball.

What data were used? One of the many datasets used in the study is a large-scale climate dataset for detecting, localizing, and analyzing extreme weather occurrences in a semi-supervised manner. The discoveries, assumptions, significantly important results, and models present in this study wouldn’t be possible without historical climate dataset, high-resolution satellite images, video, CO₂ emissions, remote sensing data.

Methods: The methods that were already used or might be potentially used in the future include but are not limited to remote sensing of emissions, precision agriculture, monitoring peatlands, managing forests, and carbon dioxide removal. It should be mentioned that there were more domains discussed in the original study, however this particular summary mainly focuses on implementation of machine learning on farms, forests, and carbon dioxide removal techniques to tackle climate change. Figure below provides the summary of methods and areas of implication mentioned above. The most impactful and interesting methods will be discussed in detail.

It might sound as a surprise; however, agriculture is responsible for 14% of the greenhouse gas emissions. Modern methods used result in massive, sequestered carbon release, such as in particular: tilling, which basically exposes topsoil to the air which is the reason behind release of locked carbon that was bound to soil. Also, as some agricultural techniques deplete soil nutrients, nitrogen-based fertilizers must be reintroduced. However, while some nitrogen is up taken by plants, the rest is being transform to nitrous oxide – a greenhouse gas 300 times more powerful than CO₂. 

Precision agriculture, which is the combination of tools and machine learning methods, can be used to make it possible for farmers to work on a large scale and not diminishing production as it happens when conventional methods are used. For instance, the hyperspectral camera-equipped robot can undertake mechanical weeding, targeted pesticide application, and insect vacuuming. Monitoring peatlands, one of the main sequestered carbon sources in the world, is essential. It is not only releasing carbon while decomposing but also is susceptible to fire. Therefore, identification and estimation of these carbon “stocks” through machine learning techniques plays an important role in potential fire risk assessment. 

One of the main points made in the study is even if all the emissions stop today, because of the carbon that is already in the atmosphere, the planet will still experience consequences of global warming. Direct CO₂ capture and consequent sequestration is a most reliable and promising solution. The main concept underlying direct air capture (DAC) is to blast air over CO₂ sorbents, and then employ heat-powered chemical processes to purify the CO₂ for sequestration. To optimize sorbent reusability and CO2 absorption while reducing energy consumption, machine learning might be utilized to speed up materials discovery, process engineering operations, such as corrosion-resistant components. 

Consequent step is to sequestrate carbon dioxide. Direct injection into geologic formations such as saline aquifers, which are analogous to oil and gas reservoirs, is the best-understood method of CO₂ sequestration. Machine learning can be utilized to find potential storage locations. Also, machine learning can contribute to the maintenance of active sequestration sites and monitor them in order to detect potential leaks CO₂ leaks.

Results: As for the results of the study, such as precision agriculture discussed in the previous section there was an actual implementation of camera equipped robots that can cover 5 acres each day and collect big datasets for continuous development using solar energy. It works for specific types of crops now, however there is a room for improvement to adapt machine learning algorithms to make them work in any kind of environment. 

In addition to this, to quantify the thickness of peat and measure the carbon store of tropical peatlands, machine learning was applied to characteristics collected from remote sensing data. Maps that are going to predict the risk of fire are expected to be developed in the nearest future using advanced machine learning techniques.

Regarding CO₂ sequestration, for more than two decades, a Norwegian oil firm has effectively sequestered CO₂ from an offshore natural gas field in a saline aquifer. Recently, machine learning approaches, as well as computer vision systems for emissions detection, have been utilized to monitor potential CO₂ leakage from wells and finding most reliable sites for the sequestration.

Why is this study important? This study gives an overview of how machine learning can be used to make a meaningful contribution in the fight against climate change, whether through effective engineering or research. Therefore, it provides valuable information and potential ideas for data scientists, machine learning enthusiast, investors, researchers that can be used to prevent catastrophic consequences.

The big picture: Climate change is a complex issue that requires a multidisciplinary approach to be solved. Greenhouse gases emissions are one of the main reasons behind global changes in temperatures, precipitation, ice glacier masses loss, and frequent fires. Mitigation of those gases requires fundamental changes in the number of sectors that includes transportation, construction, electricity systems, and industries. Unfortunately, the majority of the solutions are computationally expensive to be implemented due to big amounts of data, such as for example some climate models, where conventional statistical methods don’t work. Machine learning methods and techniques can be used to address those issues since they are less computationally expensive and more accurate. 

Citation: Rolnick, D., Bengio, Y., Chayes, J., Creutzig, F., Platt, J., Hassabis, D., Ng, A., Gomes, C., Kording, K., Mukkavilli, K., Sherwin, E., Maharaj, T., Luccioni, A., Brown, A. W., Jaques, N., Dupont, N., Ross, A. S., Sankaran, K., Lacoste, A., … Donti, P. L. (2019, November 5). Tackling Climate Change with Machine Learning. https://arxiv.org/. Retrieved December 15, 2021, from https://arxiv.org/pdf/1906.05433

Concomitant variability in high-latitude aerosols, water isotopes and the hydrologic cycle

Bradley R. Markle, Eric J. Steig, Gerard H. Roe, Gisela Winckler,  Joseph R. McConnell

Summarized by Mauricio Hollis, who is an Environmental Geology major that is also minoring in Environmental Studies at Binghamton University in New York.  He is currently a senior who will graduate in Spring 2022.  At the moment he is applying to graduate schools and plans to do research on paleoclimate.  In the future he plans to work in academia and become a professor.  Some of his hobbies aside from geology are hiking, skiing, and fitness.

What data were used?  There were three ice cores used in this article that interpreted the relationship between high latitude aerosols and water isotopes.  They were from the West Antarctic Ice Sheet Divide ice core (WDC), the Greenland Ice Core Project (GRIP), and the European Project for Ice Coring in Antarctica (EPICA) from Dome Concordia (EDC).  There were also marine sediment cores used to compare with Antarctic dust records, two being from the South Atlantic downwind of South American dust sources, and more marine sediment cores that were located just north of the WDC in the South Pacific. 

Methods:  Concentrations of δ¹⁸O, non-sea-salt calcium (nssCa), and sea-salt sodium (ssNa) were collected and analyzed from the WDC.  They were first compared on a time scale ranging from 6 thousand years ago to 67 thousand years ago comparing water isotopes with aerosol records.  Temperature, saturated mixing, δ¹⁸O, and relative atmospheric aerosol concentrations were then plotted against Southern Hemisphere latitudes.  On these figures there are three different lines representing the different trends between the Last Glacial Maxima (LGM), modern temperature, and modern temperature cooled by 3°C.  The models for the relation between high-latitude water isotopes and sea-salt amplification were then compared.  Using data from GRIP and WDC, there was a comparison of their amplifications of nssCa against δ¹⁸O concentrations.  Dust aerosol records are then compared from the WDC and EDC with marine sediment records to plot the amplification factors against the past 40 thousand years.  Lastly, dust amplification against all latitudes is predicted through the use of a rainout model.

Results:  It was found using these data that the hydrological cycle is the primary modulator of variability for dust, sea salt, and water isotopes.  Based on Figure 1A (right) there is evidence of a negative exponential relationship between water isotopes and aerosol concentrations for ssNa and nssCa.  This is indicative that as mean global temperatures decrease and more ice is formed, δ¹⁸O water isotope values see a decrease in concentration while dusts see an increase.  It is observed that there is overall less nssCa than ssNa.  This is explained by the terrigenous source of nssCa being 20°N of the marine source for ssNa resulting in lower concentrations of nssCa from 60°S-90°S due to a longer path of travel.

It is also observed that during the LGM there were higher concentrations of dust than during warmer periods of climate.  The data indicate there is evidence of smaller glacial-interglacial change for ssNa than nssCa. This is again a result of a shorter rainout pathway for marine aerosols than terrestrial aerosols.  It was also observed that δ¹⁸O isotope values from Greenland and Antarctica are very similar as they both show a negative exponential relationship with nssCa concentration amplification factor.  This is significant because they are on opposite sides of the globe with different dust sources and different regional conditions.  The data displayed for WDC and EDC show at some times, 10-100-fold amplification in dust than that collected for marine dust, which shows an amplification of 2-3-fold.  Lastly, fthe data indicate that amplification factors at the poles and higher latitudes is exponentially higher than at lower latitudes.

Why is this study important?  This study carries a lot of significance because it concludes that dust and water isotopes are both controlled by the same process, the hydrological cycle.  This has importance because it is necessary to understand the patterns of aerosol changes to further understand past radiative forcing.  

The Bigger Picture: This study disproves the theory that dust source emissions were a primary driver in ice-core records of aerosol, but rather changes in aerosol concentration at different latitudes is a result of the rainout effect.  It provides us with relevant results that can be further used to interpret how climate has changed since the LGM. 

Citation: Markle, B.R., Steig, E.J., Roe, G.H. et al. Concomitant variability in high-latitude aerosols, water isotopes and the hydrologic cycle. Nature Geoscience, 11,853–859 (2018). https://doi.org/10.1038/s41561-018-0210-9

Reconstructing Eocene Eastern Indian Ocean Dynamics Using Ocean-Drilling Stratigraphic Records

Ke Xu, David De Vleeschouwer, Maximilian Vahlenkamp, Renchao Yang, and Honghan Chen

Summarized by Olivia Cashimere, who is pursuing her Masters in Geology at Binghamton University. She is currently in her first year, and after graduation would like to work at a research museum. When she is not studying she enjoys hiking, traveling, and a variety of art mediums.

What data were used: This study focuses on two ocean drill hole archives, Ocean Drilling Program Sites 762C and U1514, located within the Eastern Indian Ocean. This study is concentrating on a 22 million year time span within the Eocene Epoch. This time period was leading up to a transition from a greenhouse to ice house climate conditions during the Cenozoic. During this time not much continental ice is seen around the globe, so not many ice related positive feedbacks are seen throughout the Eocene however, strong correlation is found between Milankovitch cycles and the climate changes. This study also uses previous studies on paleomagnetism and biostratigraphy to determine ages, and to check for ambiguity within the record.

Methods: This data collected from ODP Sites 762C and U1514 was applied to orbital scale dynamics using existing sedimentary sequences with biostratigraphy, radio-isotope dating, and magnetostratigraphy. Then stratigraphic interpretation from Site 762C is combined with an existing age depth model from Site U1514 to create a high resolution timescale for the Eocene. Downhole wireline logging with a natural gamma radiation spectrometer was also used to provide elemental data of potassium, thorium, and uranium. These help determine mineral composition, humid vs. dry environments, and astronomically forced climate signals. Using the log10 (Th/K) data a time series analysis was developed, omitting any gaps from poorly recovered core in the data. Previous studies done on Hole 762C provides data and analysis on the magnetostratigraphic record and calcareous nannofossil biostratigraphy. This data was combined to create a reconstruction of the Eocene timescale.

Results: The log10 (Th/K) analysis variability is found in cyclic patterns that roughly match with age depth, with an important note that there are four major gaps found in core recovery. Spectral analysis and depth-series provides sufficient data that sediment accumulation is steady, and power spectrum analysis identifies time series, prominent cycles, and peak frequencies exceeding 99% confidence level. Using the biostratigraphic markers previously found, the orbital tuning for Site 762C, correlated with a 405 kyr eccentricity cycle, and the paleomagnetic data was revamped to match boundaries, however, because of poor core recovery much of this data is still ambiguous and will require further studies. However with this record it reduced the number of gaps from six to four. This allowed for a supported hypothesis overall, and the combined research created an Eocene astronomical timescale that has correlated collected data across various other research methods.

Why is this study important? This study is focusing on key forcing factors that could have changed the climate dramatically during the Eocene. During this time period it is believed that there was very little continental ice across the globe, so any positive feedback from these ice sheets would be mostly nonexistent. However, we must have forcing factors that effect the environment. This study is theorizing on the possibility of astronomical forcing in deep-water circulation in the western North Atlantic. This study also identifies obliquity as the driver of Eocene climate conditions. This can be applied to current day climate systems to theorize about the current global climate warming and its effects of the planet. 

The big picture: The obliquity of Earth’s rational axis plays an important role in the deep water circulation and the movement of sediment supply. Low obliquity can be found to coincide with the cooling of ocean temperatures, and high obliquity with its warming. This idea can be used throughout may areas of study to increase our knowledge of how the Earth’s rotation changes our climate systems, and how sediments have been transported through ocean systems in the past. 

Citation: Xu, K., De Vleeschouwer, D., Vahlenkamp, M., Yang, R., & Chen, H. (2021). Reconstructing Eocene Eastern Indian Ocean Dynamics using ocean‐drilling stratigraphic records. Paleoceanography and Paleoclimatology, 36(2). https://doi.org/10.1029/2020pa004116 

The potential of the coral species Porites astreoides as a paleoclimate archive for the Tropical South Atlantic Ocean

N.S. Pereira, A. N. Sial, R. Frei, C. V. Ullmann, C. Korte, R. K. P. Kikuchi, V. P. Ferreira, K. H. Kilbourne

Summarized by Harry Janoff, who is currently a senior at Binghamton University and is majoring in Geology. After graduating from Binghamton University, Harry plans to find entry-level work in order to receive more field experience. He is unsure if he will return to grad school right now but he has definitely considered it and definitely does not want to go until he has more experience in the field. When he is not studying Geology, Harry loves to play chess and the violin.

What data were used: In their research, Pereira and their team use aragonitic coral skeletons to create records of strontium to calcium ratios and records of d18O and d13C in order to determine ancient environmental conditions of the ocean. They also used the coral’s skeletons to create the first ever d18O calibrations based on sea surface temperatures for the Porites astreoides coral species.

Methods: Pereira and their team collected Porites astreoides samples from the Rocas Atoll, located about 270 kilometers from the northeast coast of Brazil, because it is the only atoll present in Western region of the South Atlantic ocean. They collected series of sea surface temperature data for the region through the use of the NOAA pathfinder AVHRR between October 2012 and October 2013 and collected samples of P. astreoides coral from the atoll’s Cemiterio tide pool during July of 2013. The Porites samples were then cut into 5 mm thick samples and from those, carbonate samples were collected at .5 mm intervals.

The geochemical analysis of these coral samples was performed at the University of Copenhagen and involved the use of a Micromass IsoPrime mass spectrometer to measure the d18O and d13C isotopes. Coral Sr/Ca ratios were measured using a Perkin Elmer Optima 7000 DV ICP-OES and the samples were measured at a calcium concentration of ~10 mg/g.

Results: The researchers found that the two isotopes had abundance rates of 0.09‰ for d13C and 0.10‰ for d18O. They also discovered that the Sr/Ca ratios and isotope cycles displayed seasonality between 2001 and 2013. The Sr/Ca values for the coral varied between 8.86 to 9.15 mmol/mol and the mean value for the samples was 8.98 mmol/mol. d13C values for this research ranged from -1.38% to 1.05‰  with a mean value of 0.07‰ and the annual cycle for d13C contained the most positive d13C values in September and the most negative values in April or May. d18O values range from -4.26 to -3.69% and their mean value was -3.96‰. Unlike the d13C values, the d18O values were found to be  highly consistent overall, but there was a small increase in more-positive values during the years of 2006 and 2007.

Why is this study important? This study is incredibly important because knowing the cycles in d13C values and consistency of the d18O values allows us to begin piecing together the conditions where these coral skeletons formed. Pereira and their team’s research was also the first to relate these Porites astreoides values to sea surface temperatures, which will allow us to learn even more about, and maybe fully understand, the climate when these corals were formed. This study also creates links between d13C concentrations and sea surface temperature through the coral skeletons. By understanding the conditions under which these coral formed, we are able to understand climate cycles that have occurred within the Southern Atlantic ocean. Using that information, we may be able to interpret what the climate of this region was like in the past and what it may become in the future. 

Citation: Pereira, N. S., Sial, A. N., Frei, R., Ullmann, C. V., Korte, C., Kikuchi, R. K. P., … & Kilbourne, K. H. (2017). The potential of the coral species Porites astreoides as a paleoclimate archive for the Tropical South Atlantic Ocean. Journal of South American Earth Sciences, 77, 276-285.

Climate Change, Dust Storms, Vulnerable Populations, and Health in the Middle East: A Review

Muge Akpinar-Elci, Brenda Berumen-Flucker, Hasan Bayram, Abdullah Al-Taiar

Summarized by Ethan Penner, who is a geology master’s student at Binghamton University. He graduated in May 2021 with a BS in geology and is currently working on a thesis concentrated on the tectonic geomorphology of the McGregor fault, located in east-central New York. After graduate school, he plans to apply to the USGS or look for environmental consulting positions and hopes to teach in the future. Some of his hobbies outside of geology include gardening, exercising, hiking and sight-seeing.

What data were used: The data that was used in this study includes articles detailing how climate change and climate variability impact the frequency and severity of dust storms, as opposed to the more common effects of increased sea level and global temperatures, worsening air pollution, and increasing extreme weather rates, on human health. The covered articles themselves deal with data ranging from dust and air samples to illness statistics.

Methods: The authors use a systematic review to determine how dust storms affect the Middle East and its populations and searched for literature on the topic through Google Scholar as well as MEDLINE/PubMed. Articles that were utilized were  published between 2008 and 2019, written in English, and had to be full texts from scientific journals. Their search involved the keywords of “Middle East,” as well as “dust storm” and “health.” They also included individual country names following their initial review of articles (ex. “Iran, dust storm, health”). Countries were identified using the U.S. CIA’s World Factbook. Defining the “Middle East region” is difficult since the official number of countries is not set and not all resources offer the same definition of the territories. Because of this detail, Egypt was included as a part of the Middle Eastern region by the authors. The reviews studied by the authors only discussed health conditions, health outcomes, or diseases that currently affect human populations, especially those that have a strong correlation with local dust storms in the predetermined Middle Eastern region. Not all articles involving dust were included, meaning that articles discussing volcanic activity or human-induced dust production were excluded since these do not have to do with the scope of the authors’ analysis. The articles that did discuss dust exposure or dust levels but did not consider the effects on human health were also excluded. The health of animal populations was not considered when reviewing articles. The main extraction process for the utilized articles involved a review of the title and abstract, and then a review of the full text to check eligibility.

Results: In total, 534 articles were checked for eligibility, but only 31 matched the necessary criteria. Of these 31 articles, 15 were excluded because of a lack of clarity concerning the impacts of dust on human health and the use of animal subjects. Therefore, 16 of the articles were used in the study, most (10) of which focused on Iran. Two of the studies focused on Kuwait, one focused on Kuwait and Iraq, one focused on Turkey, and the final study focused on Israel. The subjects of the articles ranged from threats to human health resulting from dust composition to measurable health impacts attributable to dust storm events. Leski et. al (2011) focuses on airborne particles within collected dust samples from Kuwait and Iraq. Nourmoradi et al. (2015) deals with similar data from Iran, and both studies detected potentially hazardous airborne bacteria and fungi in the air samples. Alavi et al. (2014) details the relationship between dust and pulmonary tuberculosis and found that dust had the potential to impact TB relapse and treatment outcomes. Al-Hemoud et al. (2018) found that dust impacted respiratory diseases in humans, as well as morbidity. These are just a few of the articles that were analyzed in depth to understand a large range of data and impacts, and the overall conclusion from these texts is that dust particulates, often carrying harmful bacteria and fungi, in a region of increasing climate change leads to more severe health effects as more populations are exposed, leading to more people suffering from deadly diseases, more hospitalizations, and possibly even increased mortality.

Why is this study important? This study is vital to the conversation of climate change because it highlights the issue of dust storms, which many likely do not consider as a severe impact when compared to rising sea levels and temperatures. The hidden threats within the air and dust strewn around arid regions affected severely by climate change can cripple populations and drastically impact ways of life in the same ways as conventional ideas of climate change effects.

Overall, the authors discuss how more research should be conducted to understand the relationship between climate change, air pollution, dust storms, and health conditions. Comprehending the scope of the impacts can lead to faster and more efficient solutions to health crises across the Middle East, and further analysis of dust storms/air pollution can help scientists mitigate climate to the best of their abilities.

Citation: Akpinar-Elci, M., Berumen-Flucker, B., Bayram, H., & Al-Taiar, A. (2021). Climate Change, Dust Storms, Vulnerable Populations, and Health in the Middle East: A Review. Journal of Environmental Health, 84(3), 8-15.

Clumped isotope thermometry of modern and fossil snail shells from the Himalayan-Tibetan Plateau: Implications for paleoclimate and Paleo-elevation reconstruction

Yang Wang, Benjamin Passey, Rupsa Roy, Tao Deng, Shijun Jiang, Chance Hannold, Xiaoming Wang, Eric Lochner, and Aradhna Tripati

Summarized by Brynn Crocker, pursuing a master’s in teaching at Binghamton University with a bachelors in Geology. 

What data were used: Both fossilized and modern aragonite mollusk shells were collected from seven different lakes within the Tibetan Plateau. The fossils collected from these sites were dated to be of Cenozoic age. Clumps of carbon 13 and oxygen 18 (isotopes of carbon and oxygen) were measured to determine paleo-temperatures. The formation of the Himalayan Mountains is thought to have had a large impact on the regional climate during the time. Mollusk fossils are great archives for determining paleoclimate.

Methods: This study used X-ray diffraction to determine the values of C13 and 18O bonds (clumps) within the shells. These clumps help determine paleo temperatures and elevations. Modern shells both alive and dead were collected from the lakes in the Tibetan Plateau. The fossil mollusks were collected from fine grained sandstone, indicating that they were not transported there but lived in the freshwater lakes. These shells were then analyzed to find their clump values, which were then compared to modern temperatures. Intact Cenozoic fossil shells were then collected and analyzed to find their clump values. Intact shells were used to avoid using shells that have gone through any diagenetic alteration (changes to the fossils through heat,  pressure, and chemistry). Shells that contain calcite indicate diagenesis. Trace amounts of calcite yield temperatures of an average ~10º C lower than those with no calcite from the same strata. Shells were cleaned using HCl (hydrochloric acid) solution and then rinsed with distilled water. Modern shells were soaked in 30% H2O2 (hydrogen peroxide) to remove any organic matter. The isotope clump data was reduced using both the Henkes calibration and the Eagle calibration.

Results: After analyzing the 13C-18O clumps it was determined that southwest Tibet was warmer 4-5 Ma than today and paleo-elevation was similar to today. Using the Henkes calibration of temperatures calculated from the clump values, the temperature of the Himalayan-Tibetan Plateau ranges from 1ºC to 17ºC, with a mean of 10ºC. Using Eagles calibration, the temperature values range from 8ºC to 21ºC, averaging 16ºC. The Henkes calibration is better used for freshwater shells. There were no former long term temperature records for the lakes within the Tibetan plateau. The difference in the modern shell clump values and the fossil clump values can be explained by a change in global climate. The temperature difference between fossil shells and modern shells, after adjusting for temperature change due to sampling elevation difference, is similar to the change in the global mean temperature since the Pliocene warm period. This result tells us that the elevation during the Cenozoic was similar to today. These findings have important implications for paleoclimate and paleo-elevation reconstructions using clumped isotope data from aragonite fossil shells.

Why is this study important? This study provides additional paleo-temperature data that can be used for future paleoclimate research. The affect that tectonic events have on our climate can be significant and the significance of the Himalayan Orogeny on the climate is still disputed. This study can provide more insight on the temperatures of the surrounding areas during that time. Understanding the paleoclimate of our planet can help us better understand how it will react to things in the future.

Citation: Wang, Y., Passey, B., Roy, R., Deng, T., Jiang, S., Hannold, C., … & Tripati, A. (2021). Clumped isotope thermometry of modern and fossil snail shells from the Himalayan-Tibetan Plateau: Implications for paleoclimate and paleoelevation reconstructions. GSA Bulletin, 133(7-8), 1370-1380.

Climate change projected to exacerbate impacts of coastal eutrophication in the northern Gulf of Mexico

Arnaud Laurent, Katja Fennel, Dong S. Ko, John Lehrter

Summarized by Kristina Welsh, who is currently a junior at Binghamton University pursuing a B.S. in Environmental Science with a concentration in Natural Resources and a minor in GIS. Kristina hopes to pursue a job involving field work and travel opportunities. In her free time, Kristina enjoys camping, biking, and hanging out with her dog, Bailey.

What data were used: This study uses data from past published articles to compare present and future conditions intheGulf of Mexico. A present condition model was created using data from the Intra-Americas SeaNowcast-Forecast System. The future model was constructed using data from MPI-ESMRPC 8.5.

Methods: This study uses two 6-year physical-biogeochemical model simulations from the Regional Ocean Modeling System to represent present and future conditions in the northern Gulf of Mexico. Initial and open boundary conditions, river discharge, atmospheric temperature and pCO2 (atmospheric carbon dioxide) were variable in both models; all other factors were kept constant. The present simulation, which covers the period of 2005-2010, uses data from the Intra-Americas Sea Nowcast-Forecast System. The future simulation represents a 6-year period at the end of the century. The future model parameters were set with a 10% increased discharge from the Mississippi River, an air temperature increase of 3 ºC, and an atmospheric pCO2 increase to 935.85 µatm. Although conditions of river nutrient load were kept the same, the increased river discharge in the future model will dilute nutrient concentration results.

Results: The future models predict a summer surface and bottom water temperature increase by 2.69ºCand 2.23ºC, respectively. The salinity of surface waters decreases by 0.48 due to an increase in freshwater river discharge in the model. As salinity in bottom waters is controlled by the saltier offshore water, only a decrease of 0.02 was observed. The reduced density of the warmer and fresher water lead to an increased stratification in summers by +12.35 J m^-3. These warmer waters cause lower oxygen saturation levels and thus lower oxygen concentrations, with summer surface oxygen concentrations 3.4% lower than the present average. The decrease in surface water oxygen saturation leads to a 9.4% decrease in oxygen concentrations in bottom waters. 60-74% of the decrease in oxygen concentration is a result of saturation-dependent effects, while the other 26-40% is a result of changes in biological rates and stratification. Lower oxygen concentrations in the Gulf of Mexico leads to an increase in extent and duration of future hypoxia conditions. Hypoxic areas increase by 26% and volume increases by 39%, resulting in more frequent anoxic surface and bottom waters. The future model increased surface pCO2 and alkalinity, causing a decrease in bottom water pH range of 0.37-7.58, with large spatial and temporal variability. Hypoxic waters in the Gulf predict an average pH 7.39. Present and future conditions vary year to year due to different along shore wind directions, upwelling, and river discharge, but overall follow the same trend.

Why is this study important? This study implies how human-induced climate change will exacerbate hypoxic conditions and eutrophication-driven acidification in the northern Gulf of Mexico by the end of the century. Future hypoxic conditions will create growth and reproductive impairment to many sensitive species living in the Gulf. Changes in atmospheric CO2 can influence ocean pH and air temperatures, producing other negative effects on water chemistry, and plant, and animal life, creating a positive feedback system that will exacerbate these changes. 

The big picture: This study adds to our understanding of the risks of climate change. As this model interprets the impacts of climate change on nature and human sustainability, we can visibly see how the Earth’s oceans will change globally as well as locally. This article gives us evidence as to why we need to take action now so these changes do not occur.

Citation: Laurent, A., Fennel, K., Ko, D. S., & Lehrter, J. (2018). Climate change projected to exacerbate impacts of coastal eutrophication in the northern Gulf of Mexico. Journal of Geophysical Research: Oceans, 123(5), 3408–3426. https://doi.org/10.1002/2017jc013583

The Impact of Late Holocene Land Use Change, Climate Variability, and Sea
Level Rise on Carbon Storage in Tidal Freshwater Wetlands on the Southeastern United States Coastal Plain

Miriam C. Jones, Christopher E. Bernhardt, Ken W. Krauss, Gregory B. Noe

Summarized by James Myers who is a graduate student at Binghamton University earning his masters in teaching for earth science. As an undergraduate he majored in environmental
chemistry. Not long after he decided he wanted to become an educator and work towards
creating the next generation of environmental scientists. In his downtime he enjoys playing
guitar, camping, and watching hockey.

What data were used: Sediment cores were collected along the Waccamaw River in South Carolina and the Savannah River in Georgia. The sites were chosen because they have similar landscapes, ranging from freshwater, to moderate salinity, and oligohaline marsh. Four piston core samples were taken from the Waccamaw River, one that was found in freshwater, one in moderately salt-impacted water, and two from the Sampit River, one from a heavily salt-impacted area and one from an oligohaline marsh. Four other cores were collected along the Savannah River using a peat corer. These core sites were also from freshwater, moderately salinated, highly salinated, and an oligohaline marsh.

Methods: The cores were dated using radiocarbon analysis on macrofossils and bulk sediment which helped determine which samples were from the colonial era. Time scales were reported with calibrated years before present from 1950. Core compression was apparent within the samples, and bulk density (weight of sediment in a given volume) and accretion rates (how fast sediment accumulates) were adjusted to account for this. Carbon content was calculated using the loss on ignition method. Carbon accumulation rates were calculated by multiplying the percent carbon by the bulk density and accretion rate determined from an age-depth model. Pollen analyses were run to understand which plant species lived at these sites over time, as this method revealed what the environment must have been like if certain plants and trees were able to survive.

Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines

Rogora M., Frate L., Carranza M.L., Freppaz M., Stanisci A., Bertani I., Bottarin R., Brambilla A., Canullo R., Carbognani M., Cerrato C., Chelli S., Cremonese E., Cutini M., DiMusciano M., Erschbamer B., Gogone D., Iocchi M., Isabellon M., Magnani A., Mazzola L., Morra di Cella U., Pauli H., Petey M., Petriccione B., Porro F., Psenner R., Rossetti G., Scotti A., Sommaruga R., Tappeiner U., Theurillat J.-P., Tomaselli M., Viglietti D., Viterbi R., Vittoz P., Winkler M., and Matteucci G.

Summarized by Agnes Wasielewski, who is an MAT Earth Science Graduate student at Binghamton University. She loves Geology so much that she decided to share her passion with middle and high school students by becoming a teacher. When she’s not studying Geology or the psychology of teenagers; she spends a lot of time with her husband, three children, and three dogs. When free time becomes available, she loves to read, hike, drink tea, and take naps with her dogs.

What data were used? Researchers collected data from twenty research sites across the Alps (Italy, Switzerland, and Austria) and Apennines Mountains (Italy). All sites were located between 1300 and 3212 meters above sea level. Fourteen sites are in forests, grasslands, alpine tundra, and snow-covered areas. Six sites are in lakes and rivers. All sites considered for the paper experienced an increase in air temperature over the past two decades (1991-2015) compared to a base period of 1961-1990. A combination of data analysis on already existing datasets, projects, and new collection of data to determine results.

Methods: Temperatures taken in June were used to determine snow melting rates, the timing of the beginning of the growing season, and timing of ice-break in lakes and rivers. To analyze regional snow cover duration, data loggers combined with thermistors (special resistors used  for temperature measurements) were placed at a soil depth of 10 cm and measured hourly. If the temperatures measured remained within a certain range, the day was considered a “snow cover day”. On days where the daily mean soil temperature dropped below and rose above 0 degrees Celsius, they were labeled as a freeze/thaw cycle. The snow melting date is identified by counting the days since October 1st to the start of the freeze/thaw cycle or melting period. Soil samples were collected in September at the end of the growing season and tests are run to determine water content, carbon content, and nitrate concentrations. 

Changes in vegetation cover were calculated by estimating the percentage of each plant species in permanent grids over time. These estimates are used as a proxy for above-ground biomass. Biomass is positive when vegetation cover increases and negative when cover decreases. 

Surface water samples for chemical analysis were obtained from lakes in late summer/early autumn. May to October is considered open water season, and water temperatures combined with chlorophyll-a concentrations and zooplankton abundance are recorded. Weather stations were used to collect average air temperatures. Biologic samples were analyzed from rivers at varying distances downriver of melting glaciers to correlate community composition and diversity.

Results: At lower altitudes (~1500 meters above sea level) and latitudes (Lat. 41 degrees N), there are shorter snow cover duration (less than 100 days/year) and snow starts to melt earlier in the year. At higher altitudes (~2800 meters above sea level) and latitudes (Lat. 46 degrees N), there are longer snow cover duration periods (~250 days) and snow starts to melt later in the year. Less snow-covered days allow for increased soil temperatures and more areas for plants to grow and thrive. When more plants can grow and thrive, there are more resources available to local wildlife such as the Alpine ibex (mountain goat) and helps support their population growth. Overall, increased air temperatures and soil temperatures showed a general tendency towards increased vegetation cover for treeline, subalpine, and alpine belts but not in the snow (nival) belts. Over the last fifteen years, it is noted that plant species have been migrating from lower elevations to higher elevations in a process called thermophilization.

An increase in nitrogen deposition has positive effects on tree growth and promotes carbon sequestration (the process of capturing and storing atmospheric carbon dioxide). However, reduction in rainfall can override the positive effects. In the forests tested, a significant increase in the growing season length and a general increase in the annual net carbon sequestration was detected.

During warm and dry years, alpine streams transport concentrated solutes into the lakes and in the runoff water. Over the past decade, there has been a common trend in decreasing nitrate concentrations. Nitrogen uptake in the lake catchments has increased due to the increase in primary productivity (algae and vegetation growth). There has an overall negative trend in NO3 concentration level in rivers and lakes due to decreasing Nitrogen deposition. 

Changes in water mineral and chemical concentrations also affect the diversity and population of algae and plankton that live and thrive in mountain lakes and streams.

Why is this study important? Climate warming effects, changes in rainfall seasonality, and water availability have proven to be important for ecosystem productivity. Snow cover duration affects soil carbon and nitrogen cycling and Alpine ibex population dynamics. Warming climate change has shown to lead to an increase in vegetation cover in grasslands and carbon uptake in forests which helps remove CO2 from the atmosphere. Climate drives changes in water chemistry, lake thermal dynamics and plankton phenology can inform us of the health of the water ecosystems. High-elevation ecosystems may also be affected by extreme climatic events such as heat waves, droughts, heavy rainfall, and floods. Both long-term and short-term (extreme) events can affect mountain ecosystems. Mountain ecosystems, if properly studied and monitored, can serve as early indicators of global changes.

The big picture: Global warming affects high mountain ecosystems by increases in temperature, early snowmelt, and a prolonged growing season. With ecosystem productivity, more plant growth helps reduce global climate change by reducing the amount of carbon dioxide in the atmosphere. In mountain ecosystems, carbon sequestration depends on both water availability (precipitation) and air temperature. The understanding of hydro-ecological relationships is essential for the development of effective conservation strategies for alpine rivers. Long-term observations on benthic communities help with the assessment of the potential impacts of global change on stream ecosystems. There is a great need for strong partnerships in mountain ecosystem observation and research for multidisciplinary approaches, encompassing the distinction between different types of ecosystems. There is great potential for further scientific advances that rely on international collaboration and integration.

Citation: Rogora, M., Frate, L., Carranza, M. L., Freppaz, M., Stanisci, A., Bertani, I., Bottarin, R., Brambilla, A., Canullo, R., Carbognani, M., Cerrato, C., Chelli, S., Cremonese, E., Cutini, M., Di Musciano, M., Erschbamer, B., Godone, D., Iocchi, M., Isabellon, M., … Matteucci, G. (2018). Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines. The Science of the Total Environment, 624, 1429–1442. https://doi.org/10.1016/j.scitotenv.2017.12.155