in a climate report published in october of 2022, the united nations environmental program stated that current un policy will lead to a global 2.8°c temperature rise by the end of the century.

as threats loom and deadlines near, two fellows of the comer climate conference have worked to determine the concrete effects of climate change in their research, looking at both the past record and future predictions of the earth’s processes. 

looking toward the past

crystal rao, a geoscience graduate student at princeton university, bases her research on past environmental changes and their impacts on species using analysis of isotopes, or different forms, of nitrogen in fossils. rao uses the ratio of two common forms of nitrogen as a standard, and compares it with the nitrogen inside the tooth tissue of the megalodon shark. 

from there, she reconstructed a picture of the trophic level, or the position on the food web, where a megalodon shark is at the top. rao said, due to its high rank in the energy level, the megalodon could “basically eat anything in the ocean.”

however, this species of shark, roughly 50 feet long, suddenly went extinct 3.5 million years ago. rao said as the climate changed, the food source the sharks relied on to fuel their massive body depleted and eventually led to their deaths.

in other words, a shift in climate broke the existing food chain balance, potentially leading to the downfall of an entire species. “as climate shifts, maybe the production in the ocean could change,” rao said. “and depending on what the ecosystem responded to, there could be less food availability for those megalodon sharks.”

eyes on our climate future

while rao’s work examines a species belonging to an ancient era, another comer scientist’s work takes estimation into the possibilities of the future. 

edmund derby, climate science ph.d. student at oxford university, utilizes simple models of arctic sea ice from his past research in 2009 to examine the bifurcation or tipping point accompanying ice cover changes throughout the season. 

derby’s research presents climate from basic principles to its core behavior. in the scientific model, when atmospheric carbon dioxide exceeds a certain point, after all the arctic ice melts, it is no longer possible to gain back the ice. his model investigates this tipping point under a model when the arctic is covered in ice all year round. 

“when you’ve reached this tipping point, you don’t get a reversible change once you’ve lost your ice cover,” derby said. 

the temperature of the arctic is intrinsically connected with the rest of the world. in a phenomenon known as arctic amplification, the arctic warms twice as fast as the rest of the world. as the light-reflective ice melts, it gives way to more heat-absorbent ocean water. 

according to derby, the difference in temperature between the arctic and at the lower latitudes determines the rate of arctic temperature rise.  

this is an example of sensible heat transport: heat moves from colder to warmer objects when they are in close proximity. in the same sense, as the arctic warms up, the transfer of heat to the arctic decreases. 

however, in a changing climate, the transport of water vapor or clouds into the arctic can counteract the cooling of this cold to warm heat transfer. the water vapor causes local temperature in the arctic to rise. 

in his research, derby is adding more factors into the model to make it more realistic to the arctic ice cover, and to investigate whether the global rise of greenhouse gas will impact the ice melt at a local level. 

rao said in her field of geoscience, the past informs the future. studying the ancient past of earth’s environment builds a better understanding of the complex systems involved. “only when we can really understand or estimate the future better, then we can come up with better plans in terms of how we do climate adaptation and climate mitigation,” rao said. 

the numbers of climate change may seem small, but in the timescale of millenia, a small change now may mean a colossal shift into the future. 

through rao and derby’s research, of both the past and the future, concerns of climate change continue to loom in both the vanishing fabric of the arctic and the demise of a species. 

as the earth warms, researchers at the penn state ice and climate exploration research center (psice) at penn state university are interested in how we can expect glaciers, those dense bodies of ice that move under their own weight, to react to a drastically changing environment.

extreme hurricanes and floods and increasing wildfires and drought make the impact of climate change increasingly obvious, but what happens to glaciers and ice sheets is important for the future of so many coastal cities that lie in potentially devastating floodplains. 

veteran geoscientist richard alley of penn state university, revealed a bleak future during the annual comer climate conference this fall, one where a changing climate will affect the earth and all of its inhabitants, not just humans, at a systemic level. 

alley said that to study climate science is to steep one’s self into worry and anxiety about the future. 

but it presents solutions to those very worries, as well.

“i suspect the students need a sign over the door that says ‘we are the ark,’” alley said. “we’re going to get through this by preserving [various] species so we can get them back out, cause some of them are in such deep trouble now and they’re going to need help.”

predicting a worst-case climate scenario

by 2100, projected global sea-level rise could be slowed to a half meter lower than prior projections, but only if global temperature increase is kept at 1.5°c instead of 2°c, according to estimates by the intergovernmental panel on climate change.

alley considers the projection a modest estimate and seeks, along with his research group, to estimate a worst-case scenario resulting from no climate action. 

“we can hope, but i think the biggest thing is to limit co2, and then as much collateral damage [as possible],” he said. 

co2 levels drive global warming and many scientists calculate that increasing levels over the past decades are already rolling 2°c of temperature rise into the atmosphere. alley said that carbon dioxide spells devastating damage for lots of organisms that live in sea water even before those rising tides can impact humans. 

alley has studied the great ice sheets to predict the future climate and sea level change. he participated in the un intergovernmental panel on climate change and was the co-recipient of the 2007 nobel peace prize the ipcc received along with former vice president al gore. alley was also the first recipient of the stephen schneider award for climate communication. 

sierra melton, a geosciences ph.d. student of alley’s, currently focuses her studies on one of the largest glaciers in greenland, helheim glacier. the glacier drains from the greenland ice sheet straight into a fjord and – upon touching the water – breaks into icebergs. melton is studying the complex hydrology behind the phenomenon as it is not totally understood by researchers yet.

“with more melting and warming, and glacier collapse, studying helheim is kind of one way to look into the future where these glaciers might look like,” melton said. 

 “it’s really a very interesting glacier because there’s a lot of meltwater, both on the glacier and, and draining from up the glacier,” she said.

climate change research was the only major avenue melton ever considered for a career path, long before she started her work on large-scale glaciology projects.

“i don’t know exactly why but i was just always concerned about it,” melton said. “even for one of my birthdays in elementary school, i asked for donations to the world wildlife fund to save the polar bears. so yeah, so i guess i’ve always been concerned about climate change.”

“i am very concerned about what climate change is going to do for our future. and that’s why i’ve gotten into this work” she said. “and i think it does motivate me more than it makes me anxious.”