Climate change causes ecological issues in Alaska

[Editor’s note: This story is the fourth part of the multi-part series “Climate Crisis” examining the causes and effects of climate change that began with Issue #1 and concludes in Issue #6. Several staff members took it upon themselves to interview and conduct research. The results of their combined efforts follow.]

Alaska’s ice is melting.

According to scientists at Alaska’s Climate Science Center, trends that have been documented throughout time indicate that Alaska’s climate is changing at a rate faster than that of the rest of the United States.

“Generally, the arctic is warming at roughly twice the rate of the rest of the planet as a whole,” Dr. Jeremy Littell, lead research ecologist at the Alaska Climate Science Center, told the Plainsman Press in a recent interview. “The northern most part of Alaska is warming faster than the middle, which is warming faster than the part closer to the north pacific in British Columbia.”

Dr. Littell’s work is focused on specific aspects of climate-related impacts. His training is in eco-climatology. He studies climate and how it affects ecosystems.

“I do work on how tree seedlings respond after fires and how they respond to the tree line moving up into the higher arctic, ” Dr. Littell said. “I work for the U.S Geological Survey, which is part of the Department of the Interior. I’ve been involved in climate impacts on forests for 17 years.”

In 2000, Dr. Littell began studying how climate affects forest fires. He received his master’s degree at the University of Montana while studying climate and fires at Yellowstone National Park. He also has received a PhD from the University of Washington, where he studied modern records of climate and fire, as well as the climate’s affects on tree growth in the Northwest.permafrost

Climate Science Centers are a partnership between universities and the federal government.  There are eight climate science centers across the United States. The Alaska Climate Science Center is affiliated with multiple universities within the state. Although the center is based in Anchorage, they are most scientifically affiliated with the University of Alaska at Fairbanks when it comes to geophysical and climate research.

According to Dr. Littell, there has been a series of effects that are direct results of a warming climate in Alaska. Most of these effects take place in the northern most parts of Alaska and in the Northwest. Most of the communities that are affected are in the Northwest, close to Alaska’s coastline.

One change that affects these communities in Northern Alaska is the decrease in the phenology in which the ice becomes a thick ground for hunting ice seals. According to Dr. Littell, communities in this area rely heavily on the thickness of the sea ice.

“The thickness of that ice is decreasing,” Dr. Littell said. “And many of those communities rely traditionally on animals that are ice dependent. So their access to some of those traditional foods is limited by the changes in the sea ice.”

Scientists, over time, have used tools that measure these changes in the thickness and presence of the ice. According to Dr. Littell, the data that is recorded in the communities dates back into the 1970s when satellite imagery began recording aerial observations.

Dr. Littell says that many lines of evidence prove a trend.

“Coastal observers, buoys, satellites and other instrumentation converge in the measurements that they make,” he explained. “These make you have pretty good confidence that what you’re observing is real and not just an artifact observation.”

Another concerning effect of climate change, according to Dr. Littell, is the thawing of permafrost. Most of the land in the northwest parts of Alaska has permafrost. Permafrost is a mixture of water and soil that has frozen.

According to Dr. Littell, as the climate of Alaska warms, the phenology of the permafrost has become shorter, resulting in a longer thawing period.

“If you live on the coast, part of the stabilizing effect of your soil and ground along the coast was the fact that it was frozen,” Dr. Littell said. “Now it’s not frozen, or it has been thawing for more of the year. This results in an increased tendency for erosion. The thawing permafrost and melting sea ice then interact.”

Dr. Littell says that in some cases, the ocean will freeze and thaw earlier in the year, along with the land surface. This increases the potential for storms that erode Alaska’s coastline. He says that areas on the coastline in the past were not affected by storms as much because the sea ice would protect the land from violent waves.

“The frozen permafrost soils protect the land from eroding as quickly,” he explained. “There are villages that are struggling with geologically very fast changes in the coastline.”

According to Dr. Littell, buildings that have been built on historically non-thawing permafrost have been left with failing foundations. This change can also result in sinkholes, as the ice that may have once taken up a large volume of the permafrost has melted, resulting in sinkholes.

“Here, we have what we call a thermokarst landscape,” Dr. Littell said. “This is permafrost that has thawed, creating a big hole in the ground. If your building is on that slump, you’ve got a big problem.”

Alaska’s warming climate also contributes to the phenology issues that arise among the state’s ecosystems. Dr. Littell says that wildlife is affected in many ways by the changing variances of seasonality. As you move north, the more rapid the change.

“One example is caribou and moose,” he explained. “The differences between the two are in what they eat. Caribou food is associated more with open tundra ground. They eat lichen and a variety of other plants that live in the open tundra, while moose are an edge-of the-woodland critter that eat mostly twigs.

Dr. Littell says that a changing climate affects food resources of wildlife in different ways. He says that as these food sources move north, portions of land that used to be ideal for caribou has become the home to moose. This effect can become a burden on communities that have traditionally depended on moose, caribou and other plants and animals as a food source, though this change happens slowly.

“Most of these communities are not on the major road system,” Dr. Littell said. “The only way into and out of these villages is by water and air. You have to understand that these food sources are part of their cultural identity. If your community depended on caribou, and if there are quite a few less caribou, then you are having to transition the foods that you include in your diet.”

Dr. Littell says there is evidence of an increase in temperature of 7/10ths of a degree Fahrenheit per decade since the 1970s. He says there is evidence in Alaska’s landscape that dates back to the 1920s that indicates warming temperatures. This evidence includes changing glaciers, changes in seasonality, changes in vegetation habitats and changes in natural wildfire patterns.

“All of those things are in agreement that these effects are driven by warming temperatures and less so by potential changes in precipitation,” Dr. Littell added. “You can’t explain that rate of change in the climate system without considering the impacts of humans and greenhouse gasses. The data very clearly points to a chain of causes that starts with greenhouse gas emission and concentration in the atmosphere.”

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