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Climate Change in Alaska

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Jennifer Guerra
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Cheryl Li
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6 December 2019
whClimate Change in Alaska
Global temperatures increased 1.5 degrees Fahrenheit between 1970 and 1980, and an
additional degree from 1980 to 2000. Although the warming occurred simultaneously with a
climate pattern, Pacific Decadal Oscillation, it should not be considered the cause of the global
temperature increase. Pacific Decadal Oscillation, PDO, which affects the Northern Pacific region,
lasts for 20 to 30 years and creates various changes in climate, especially as they shift from warm
to cool phases or vice versa. Changes in the upper atmosphere affect hurricane activity in the
Atlantic and Pacific, cause droughts and flooding along Pacific coastlines, affect the growth of
aquatic ecosystems, and affect temperature changes globally. From 1951 to 1975, the PDO was in
a cold, or negative phase. During cold phases, cold water from deep in the ocean is mixed with the
warmer water close to the surface, keeping global temperatures lower. A change in the system
occurred in 1976, and from 1977 to 1999 the PDO system consisted of a warm, or positive phase.
During the warm phases, Pacific coastal waters are warmed, accelerating the effects of global
warming. Over the last two decades, the phases between warm and cold began changing every few
years, instead of lasting for decades. Currently, we have been in a warm phase since 2014.
Scientists aren’t sure what causes changes in PDO, but changes appear to be tied to Rossby waves
and the Aleutian Low. These patterns, warm or cold, can also intensify or decrease La Nina and
El Nino Southern Oscillation events.
Barrow, Alaska is considered ground zero for the effects of climate change, as the warming
in the Arctic occurs twice as fast as the rest of the world. Temperatures in the summer have
increased by 3 degrees, and six degrees during the winter months. From 1978 to 2007, ice in the
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region during summer months shrank by nearly 40% and is expected to be gone before 2050.
Spring snowmelt is occurring sooner and more rapidly than expected. Coastal erosion has
accelerated, as the receding ice allows for larger storms, with bigger waves crashing into the
shoreline. On land, the loss of ice on river banks is causing erosion, filling waterways with silt.
One of the most disastrous effects of the warmer temperatures is the thawing of permafrost. The
softening soil has allowed for an increasing number of trees in the tundra and causes billions of
tons of methane to be released, furthering the effects of global warming. Additionally, thawing
allows the draining of tundra lakes, which affects the supply of potable water for wildlife and
humans. The warmer temperatures have also affected the species of fish and shellfish in the area
and brought an influx of insects, which are affecting native plants and animals. On top of this,
summer thunderstorms have increased, and the season has been warmer and drier. This has caused
the wetlands to dry out and there has been an increase of forest fires over the last decade.
Over the summer, temperatures were warmer than 9 degrees Fahrenheit in the Chukchi
and North Bering seas, causing ice to melt at increasingly rapid rates. In 1979 there were 7.05
million square kilometers of ice in the Arctic. In 2012 that number had dropped to 3.57 million
square kilometers, the lowest ever recorded. The second biggest losses occurred in September of
2019, recorded at 4.32 million square kilometers. The average loss of ice per decade is currently
equivalent to 12.85%, a significant increase when compared to the rate of 3.4% in 2004. There
have been increasing years with plunges of ice melt, and as more is lost, it becomes thinner, melting
easier the following year. The ice surrounding Alaska, which usually lasts until the end of May,
was gone in early March of this year. The ice is freezing later in the year, and melting sooner,
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further affecting the melt rate. In 2008, the previously impossible voyage through the Northwest
Passage was opened. Now commercial ships, research teams, and passenger ships filled with
tourists are becoming more common. The coast guard has stepped up its presence in Alaska,
monitoring the waters for ships from Russia and China, advancing on the U.S. The Northwest
Passage by U.S. view are international waters, but to Canada, they belong to them. After some
tension between the two countries, they have come to a temporary agreement, but tensions between
all the countries trying to make claims in the artic may not stay peaceful. The people of Alaska are
also concerned that the influx of boats will cause even more problems with the waters they fish
and hunt in, too much traffic causing wildlife to venture further away. Additionally, the thawing
ice isn't just warming the water, but is also decreasing the salinity. The freshwater rivers of Eurasia
are draining into the Arctic Ocean, causing further warming and desalination, which could disrupt
the thermohaline circulation of the ocean. Thermohaline circulation, which is already being
affected by CO2 emissions, is directly affected by changes in the density of the water, which are
affected by temperature and salt. It carries warm water from the tropics to the Arctic region,
causing cool water to sink and flow back towards the equator. The constant flow of changing water
temperatures helps maintain global climate conditions. The loss of this system would be
catastrophic worldwide.
Alaska is home to 40% of all the native tribes in the nation. Their livelihood is dependent
on the ability to hunt caribou, seals, walruses, polar bears, whales and fish. The receding ice has
made hunting more difficult and dangerous. Hunters and fishers are having to travel further and
on thinning ice, sometimes falling through, and the occurrence of diseases are increasing in the
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vegetation and animals. The Northwestern coast of Alaska has experienced sea level rise and an
increase in the number of major storms. The loss of ice along the coasts have made them more
vulnerable to the storms as massive waves crash into the shoreline, causing coastal erosion,
considerable damage, and flooding. Coastlines in some areas have eroded so much that more than
half a mile of shoreline has been lost to the sea. Unfortunately, many of the cities and villages in
Alaska are built on rivers and coasts, where the impact of erosion and loss of permafrost is more
drastic. The thawing of permafrost under roadways, homes, and other infrastructures is making the
ground sink unevenly below them. The shift is causing the crumbling of roadways, bursting of
pipes, and affecting structural integrity, causing sinking and collapse. These events are polluting
potable water with salt water, sewage, and other contaminants such as pesticides and mercury.
There is a need to relocate more than 30 villages, but the cost to do so, along with restrictions of
land and roadways, is making it extremely difficult. Furthermore, as snow disappears sooner, so
do ice roads and the ability to use dog sleds, which are critically important to Alaskans. As the
weather gets warmer, ice roads will need to be replaced with gravel roads, which could cost more
than $2.5 million for each mile.
Changes to Alaska’s climate are taking their toll on the wildlife of Alaska and the people
that depend on them. Warming waters and the loss of ice have brought new species to the area.
Various whales; including humpback, bottlenose, sperm, and killer whales have been spotted. The
killer whales have been killing the narwhal and beluga whales, which are native to the area and
hunted by indigenous Alaskan’s for food and other resources. The declining ice is also reducing
the available habitat for seals, walruses, and polar bears. Animals which are also an important
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source to the indigenous Alaskans, who hunt them for food and use seal hides on the bottoms of
their boats, as aluminum rivets pop in Alaskan waters. Native Alaskans have reported their usual
weeks to months of good walrus hunting have declined to only a few days. The habitat loss has
been especially harmful to polar bears, who had declined by 40% between 2001 and 2010, adding
them to the list of threatened species. Seals are their main source of food, and the melting ice
means that they will have to move much further to find them, causing a huge increase in the number
of calories burned. Once a polar bear loses too much weight, muscle mass starts to decline, making
it more difficult to hunt for food. Polar bears are starving, and studies project a loss of 2/3 of the
species by 2050. Puffins are another species being affected by the changing climate. Normally,
their diet consists of white hag and herring, but these fish have moved to cooler deeper waters.
Adult puffins have tried feeding their young a different type of fish, but they are unable to swallow
them, and it is leading to starvation and death.
Fisheries in Alaska provide more than every other fishery in the U.S. combined. Exports
of Alaskan seafood bring nearly $13 billion a year. Typically, commercial fisheries use the
southeastern shelf of the Bering Sea. The cover of ice protects marine life from predators and algae
grows beneath it to feed zooplankton in the spring, an important food source for juvenile fish.
Without ice, there are no algae to feed the zooplankton, decreasing the survival of young walleye
pollock and cod. The changes in the ecosystem are causing a decline of harvestable fish. While
many species of fish will be able to move further north, the survival of boreal and juvenile fish are
more limited, as are unable to survive the colder, saltier water, and the risk of predation. The
change in the ecosystem is also affecting certain crab populations. The Alaska Department of Fish
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and Game canceled the harvesting of the Bering Sea Tanner crab in 2019, as well as 2020, due to
a decline in the crab population. In other waters, they have had to cancel harvests of the blue and
red king crab for 2020. Sea levels are rising, water is warming, ice is decreasing, and the chemistry
in the water is being affected, becoming more acidic. These changes are causing an increase in the
existence of disease pathogens and algal blooms, which release toxins into the water and reduce
oxygen. They can infect fish and shellfish and will affect human health when consumed. The
changes to the ecosystem are causing fish to move and change their behavior, forcing fishermen
to travel further, sometimes not finding the fish they need. Changes to freshwater are also posing
a problem. Alaska’s Yukon River has seen the invasion of a parasite that is harmful to salmon. As
temperatures warm, the growth of the parasite will expand, further impacting the fishing industry,
and those that depend on it.
Alaska’s boreal forests are changing as well. In some areas, the warming air and soil have
increased plant growth, seen in black spruce. Others, such as the white spruce growing in Alaska’s
and floodplains, had poor growth responses to these changes. When the trees were healthy, they
absorbed pollutants from the atmosphere. Unfortunately, as vegetation dies, those pollutants are
released back into the air, adding to those released from melting permafrost. Toxic gases are
increasing, which will further affect warming. From 1974 to 2008, the yearly average of carbon
dioxide in the atmosphere rose by 16% and methane by 5%. The topography is changing, melting
permafrost is creating irregular surfaces and marshy hollows. The effects further allow the flow of
water, leading to more melting and uneven ground, which is causing trees to tilt or fall over.
Between 1994 and 1998, there was a loss of 35% of the permafrost in the birch forests of the
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Tanana Flats, irreversibly changing the area into a marshy bog. Many of the lakes and ponds are
shrinking as warmer temperatures cause evaporation and thawing permafrost causes drainage.
Others, are expanding as the permafrost causes the ground to collapse, filling the area with polluted
water. The loss and contamination of lakes and wetlands have reduced the available nesting
grounds for migrating fowl. As nesting grounds dwindle, birds that depend on them will diminish
in numbers globally. Grizzly bears and coyotes are moving north, increasing predators in the
forests. For the snowshoe hare, the absence of snow leaves it without the protection of camouflage.
A decline in their population would affect the entire forest ecosystem.
As temperatures rise and permafrost thaws, new trees and expanding shrubs are taking
over the vegetation in the tundra. This is causing a decrease in lichen, which feeds the caribou in
the winter. The rising temperatures have also brought an increase in the number and diversity of
insects. There are concerns that with the warmer temperatures, non-native pests, such as the spruce
aphid, will be able to reproduce and spread as they lack predators in the area. A few of the other
problem insects include the spruce bark beetle, ticks, and flies. Spruce bark beetles have been
rapidly increasing in numbers. With warmer winters, they aren’t dying like they used to, and the
warmer summers allow the larva to develop within one year, instead of two. These beetles cause
damage to almost every aspect of the tree, including the roots, trunk, and parts needed for
reproduction. They kill the tree and impair the ability for new trees to grow. In southcentral Alaska,
they are responsible for killing more than 3.7 million acres of white spruce. Tick populations also
increase when winters aren’t cold enough. A single moose can carry tens of thousands of ticks on
their heads alone. As this parasitic pest feeds on a moose, it weakens their immune system. The
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weakened immune system can lead to death, especially in young calves, and cause a decline in the
species. Warmer temperatures are increasing the migration of moose populations, which are
moving further north and bringing ticks with them. The invasive parasite will mean big trouble for
animals and people in northern Alaska, as they feed on wildlife and spread diseases like Ehrlichia,
Rocky Mountain spotted fever, and Lyme disease. Additionally, Alaska has seen a large increase
in flies. These flies are making caribou ill, adding to the many factors affecting their health and
well-being. The loss of caribou would be detrimental to the ecosystem, as they are important food
sources for bears, wolves, and Alaskans.
Along with these changes, warming temperatures and drought have also led to an increase
in forest fires and have extended fire season by more than two months. Alaska lost a record 6.5
million acres of forest in 2004, and another 5.1 million in 2015. This year, the season started early,
and fires have strangely continued to burn, long past what has been normal. On June 5th, 2019 a
forest in the Kenai National Wildlife Refuge Wilderness near Anchorage was ignited by lightning.
The area was considered low risk and so was only being monitored. Within a week the fire grew
from approximately 5 acres to nearly 13,000 Acres. By June 19th, it had reached nearly 16,000
acres. The smoke and pollutants caused a temporary closure of the highway due to poor air quality.
By the last week of June, the fire had expanded to more than 62,000 Acres. By mid-July, it had
consumed more than 100,000 acres. Rain during the end of July help to suppress the fire and it
was believed to be under control. Unfortunately, on August 17th, a wind storm occurred bringing
with it 35 mile-per-hour winds that reignited the fire, spreading it south and into the Skilak Wildlife
Recreation Area. Within a week the fire had consumed another 50,000 Acres. As of September
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29th, the fire had consumed 167,164 acres. Although the fire is considered 90% contained, it is
estimated to not be fully contained until December 31st. This is only one of the 663 fires that have
occurred this year, consuming more than 2.5 million acres of land. While the effects of forest fires
improve conditions for moose and plants previously unable to grow under the forest canopy, it
means the loss of more lichen, further reducing food availability to winter caribou.
The changes to Alaska’s ecosystem are already devastating the state. The cause and effect
of climate change are circling each other, causing conditions to worsen. Their location at the top
of the world makes them more vulnerable, while their proximity to China increases the pollution
in their atmosphere. Alaskans are already experiencing changes requiring them to move, but
suitable options are limited. Furthermore, with the continual change to the ecosystem, moving
might not ensure their safety. As the earth continues to warm, the effects will become more severe,
forever changing the land and life they know. Even with most of the world trying to decrease their
CO2 emissions, it will not be enough to stop the changes in Alaska. Especially when our nation’s
leader continues to deny a need for change, and makes decisions that will move our emissions in
the opposite direction.
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