Weather and climate are key physical drivers of ecosystem structure and function. Because global climate models indicate that climate change and variability will be greatest at high latitudes, climate monitoring is critical to understanding the changing conditions of park ecosystems. Some potential effects in Southwest Alaska parklands include a reduced snowpack, earlier lake-ice breakup, warmer winters, and wetter summers. These changes will likely affect the distribution, abundance, growth, and productivity of plants and animals.
Lake Clark National Park and Preserve, located in Southcentral Alaska, straddles three climate divisions, Bristol Bay, Cook Inlet, and the Central Interior. It is divided southwest to northeast by the Alaska and Aleutian mountain ranges (Bieniak et al. 2015). The Bering Sea and the Pacific Ocean significantly influence the climate of this region by moderating the transfer of energy and water vapor to and from the atmosphere resulting in a maritime influenced climate on the south and west sides of the park. To the northwest of the Chigmit Mountains the climate patterns are more typical of Alaska’s western interior that is often colder in the winter and warmer in the summer.
We operate weather stations in each of Lake Clark’s three climate divisions where the patterns of annual temperatures show differences due to their association with climate divisions and altitude. The snowy, high- altitude station of Chigmit Mountain straddles the crest of the range where it is cold most of the year (Figure 1).
In contrast, the Silver Salmon Lakes station on the Cook Inlet coast has moderate temperatures year-around and the Port Alsworth station shows a similar pattern that is sometimes influenced by the seasonal ice cover on Lake Clark and the Bristol Bay. Finally the Stony Station shows the broadest range of temperatures due to it’s location in the Western Interior climate division (Figure 2).
Patterns in sea surface temperatures and other climate dynamics will affect Southwest Alaska’s weather this spring and summer. Typically, the northern seas that surround Alaska (the Bering, Chukchi, and Beaufort) are mostly ice-covered in winter (see NASA's visualization of sea ice data). However, this year saw the lowest ice cover since satellite observations began in 1979. The Bering Sea, which is much warmer than normal, has had areas of open water that are historically unprecedented. So far this year, the Northern Pacific is only slightly warmer than normal, with a positive Pacific Decadal Oscillation, a long-term index of sea surface temperature (Namias 1959, Mantua and Hare 2002). Due to these and other climate influences, Southwest Alaska’s 2018 temperatures are predicted to be above normal this spring and summer. Precipitation is more difficult to predict and thus, predictions have higher uncertainty. Regional forecasts range from weeks to several months and are regularly updated from multiple models they can be found at: cpc.ncep.noaa.gov/products/predictions.
Bieniek, P., U. Bhatt, R. Thoman, H. Angeloff, J. Partain, J. Papineau, F. Fritsch, E. Holloway, J. Walsh, C. Daly, M. Shulski, G. Hufford, D. Hill, S. Calos and R. Gens. 2012. Climate Divisions for Alaska Based on Objective Methods. Journal of Applied Meteorology and Climatology 51:1276-1289.
Mantua, N. and S. Hare. 2002. The Pacific Decadal Oscillation. Journal of Oceanography 58(1):35-44.
Namias, J. 1959. Recent seasonal interactions between North Pacific waters and the overlying atmospheric circulation. Journal of Geophysical Research 64:631-646.
Discover More about Climate in Alaska's Parks
Real time data from Inventory and Monitoring Network weather stations can be found at:
Western Region Climate Center
Quarterly climate predictions from the National Weather Service
Long term climate projections can be found at Scenarios Network for Alaska Arctic Planning
NASA Arctic Sea Ice Minimum
More on the Pacific Decadal Oscillation
More on snow and ice cover can be found at the National Snow and Ice Data Center
Last updated: March 20, 2018