Arctic Climate Change’s Effect on Caribou Migration

by Kelsey D’Ewart

The freezing and thawing patterns in the Arctic have been increasingly affected as a result of global temperatures increasing, resulting in earlier later freezing and earlier thawing. This is forcing phenology changes in many Arctic species. Particularly, there has been a change in migration patterns in many species due to the lack of frozen bodies of water. This can lead to longer, more strenuous, and more dangerous migrations that can result in higher mortality rates. Leblond et al. (2016) tracked the ice thawing and freezing times for bodies of water in the migration path of caribou Rangifer tarandus Northern Quebec from 2007−2014, allowing them to determine if the change in ice melt was affecting the caribou’s phenology. Their hypothesis was that the caribou would travel extra distance in order to avoid swimming or water that was not completely frozen. They assessed four different parts of the migration: previous data for freezing trends, the caribou’s response to the change in freezing trends, fine-scale caribou behavior and phenology, and possible future movement using climate change projections. Continue reading

Any Reason to Expect a Tipping Point with Arctic Sea Ice?

by Emil Morhardt

Williamson et al. (2016) examined the satellite data looking for signs of a tipping point in Arctic sea ice loss, but found none (my Jan 1 post). About the same time, Notz and Stroeve (2016) looked at the same data and did a simple linear correlation between September Arctic sea ice area and cumulative CO2 emissions since 1850. Voila! There was a strong negative linear correlation between the two showing a sustained loss of 3 ± 0.3 square meters of September sea ice area per cumulative metric ton of CO2 emission. Their title summarizes the result clearly: Observed Arctic sea-ice loss directly follows anthropogenic CO2 emission. If this linear trend continues and there is no tipping point—and there is no reason to expect one—we can make a pretty good guess about the timing of the future of Arctic sea ice to the extent we can predict CO2 emission levels. At the rate we are going, September Arctic sea ice will be completely gone before mid-century (and global average temperatures will have risen more that 1.5ºC.) Furthermore, we can now get a feeling for how much our personal use of fossil fuels and the energy derived from the directly affects Arctic sea ice; the average CO2 release from personal use is several metric tons,  Continue reading

National Security Threatened Due to a Warming World

by Chloe Rodman

Jeff Goodell (2015) writes in Rolling Stone Magazine that 30 of the United States’ domestic military bases are in jeopardy due to climate change and rising sea levels. These stations either must be relocated in the near future or put out of commission because not only are they sinking into the ocean, but the compounds become flooded with each storm, making work almost impossible. Because of these recent trends, the Pentagon, as well as President Obama, believe that “…climate change poses immediate risks to our national security.” While many powerful and important members of the military and government believe action must be taken regarding climate change, some members of congress do not agree. These congress members, some of whom happen to be on various military committees, castigate those who believe in climate change or those who liken it to other global disasters such as terrorism or infectious disease. Continue reading

Modeling CO2 and CH4 Fluxes in the Arctic using Satellite data

by Rebecca Herrera

The peatlands and tundras of the Arctic perform vital ecosystem services to the earth through their ability to sequester carbon (CO2) and methane (CH4) and function as a carbon sink. The ability of the permafrost in the peatlands and tundra ecosystems of the Arctic to continue to function as a natural reservoir for carbon and methane may be disrupted by rising global temperatures that increase the rate of soil decomposition. Watts et al. (2014) integrate a terrestrial carbon flux (TCF) model to include a newly developed CH4 emissions algorithm. The new TCF model simultaneously assesses CO2 and CH4 fluctuations and the corresponding net ecosystem carbon balance (NECB), which is contingent upon gross primary productivity (GPP) subtracted from ecosystem respiration. The integrated TCF model uses data gathered through satellite remote sensors to assess fluxes in CO2 and CH4. Continue reading