Report details local climate chaos and solutions
Juneau receives 20 inches more rain per year than it did a century ago, snowfall could drop nearly 60% by the end of this century, and the Mendenhall Glacier will likely disappear from sight at the visitor center in Juneau. 2050, according to a new report specific to Juneau. climate report released on Monday.
The changes also pose significant threats to local food sources, such as salmon and crab species, whales, and tour operators taking advantage of viewing cruises and infrastructure running from a large percentage of downtown buildings. from Juneau to the Mendenhall sewage treatment plant.
However, the report released by the Alaska Coastal Rainforest Center at the University of Alaska Southeast goes beyond simply listing all the past and future changes and their mostly negative impacts, detailing the remedies already tempted and potentially mitigating future actions.
“Long before Western observations of climate change, indigenous peoples of Southeast Alaska observed and responded adaptively to changes in this dynamic environment, including rapid glacial advances and retreats, uplift and falling sea levels and a host of extreme events well documented in oral histories,” wrote Thomas Thorton, one of the study’s 22 co-authors, in an introductory post.
“Now, a new era of climate change unprecedented in human history is upon us, and Juneau, as a modern capital and regional hub, must respond and adapt accordingly. The citizens of Juneau launched an innovative carbon offset program, its scientists conduct impactful research on forests, temperate forests and glaciers, and its downtown port holds the world’s first shore power outlet for cruise ships to reduce harmful greenhouse gas emissions.
A webinar on the study hosted by some of its authors is scheduled for Thursday at 9 a.m.
For skeptics who argue that climate change has historically occurred over time periods measured in decades or millennia, the new Juneau-focused report agrees that’s true — from a certain perspective.
For example, the increase in average annual precipitation from about 160 inches in 1920 to 180 inches in 2020 did not occur in a straight line.
“The mid-1930s to mid-1940s were wet, then the 1950s to 1970s were relatively dry, and since the mid-1990s wetter conditions have returned,” the study notes. “And within those ten or two intervals, there are individual years that are exceptionally wet or dry.”
However, the main conclusion, as with most modern climate change impacts, is that historic amounts of global change are likely to continue and often at increasing rates in the future.
“This year-to-year and decade-to-decade variability will continue into the future even if the long-term rainfall trend continues to increase,” the study notes.
The changes will be harmful to local animal life, studies say, ranging from tiny seabed organisms endangered by increasingly acidic waters to mountain goats who may only find mountain tops cool enough to survive. exist during the warmer months.
Damage to humans will range from Alaskan Natives increasingly unable to survive on traditional food sources, to potential loss of homes due to landslides and floods, to all-out struggles involving everything from transportation to mental health.
Similarly, while the overall annual temperature increase of about 1 degree Fahrenheit since 1925 is not huge, the changes are significant during the winter and summer months.
“Taken together, retreating glaciers, increased flooding, and greater avalanche threat are all related to these larger-scale changes in the environment,” the study notes. “Other observed changes that have cascading effects, such as the duration of snow cover at low elevations, are directly attributable to seasonal changes in temperature and total precipitation. These changes will continue in the future, perhaps on a much larger scale.
There are also quirks that run counter to global trends, such as sea level rise, which has some major coastal cities worried about seeing significant portions possibly submerged. But Juneau is experiencing a relative sea level drop that has been occurring for centuries due to the region’s land surface uplift rates.
This finding gets stranger looking to the future, predicting that sea levels could drop 2.9 feet or rise as much as 4.3 feet by 2100 depending on the amount of global gas emissions. Greenhouse effect.
The report details nine key findings, including seven impacts and two related to responses:
■ More precipitation: Juneau is on a long-term rising trend, with average annual precipitation increasing by about 20 inches over the past 96 years
■ Rising temperature: A general overall increase is marked by significant increases in winter and summer, but much less in spring and fall.
■ Less snow: The average winter accumulation in Juneau has decreased between 1940 and 2020, and continued warming is expected to reduce snowfall near sea level.
■ Surface uplift and sea level rise: Sea level rise is currently exceeded by land surface uplift caused by retreating glaciers, but sea level rise could exceed land surface uplift later this century.
■ Ocean warming: Warming sea temperatures are expected to significantly stress many parts of ocean ecosystems – such as marine mammals, fish and seabirds – and could promote algal blooms.
■ Increased ocean acidification: The decline in marine pH is likely to cause widespread negative social and ecological impacts on marine ecosystems.
■ More landslides: Landslides are expected to increase as the climate becomes warmer, wetter, and characterized by more extreme precipitation events.
■ Answer – reduction of greenhouse gases: The City and Borough of Juneau have developed a climate policy and proposed to implement strategic climate actions to reduce greenhouse gases by obtaining 80% of Juneau’s energy from renewable sources by 2045 .
■ Response – residents take action: Juneau nonprofit organizations and tribal and local governments are taking action to mitigate and adapt to climate change.
“The fact that traditional wild food sources are now being classified so that Indigenous peoples can better manage harvests within the limits imposed by climate change is a testament to the resilience of the Tlingit and Haida peoples,” notes the report on the second element of response. . “Faced with the bitter reality of change, the authors of the Climate Adaptation Plan have chosen to confront the situation head on and find ways to adapt. The wider community can learn from this, as everyone in the CBJ can expect to have to adapt to changes in their food supply brought on by climate-related factors.
• Contact journalist Mark Sabbatini at mark.sabbatin[email protected]