National Park Service

Southwest Alaska Network (SWAN)

Weather, Climate, & Air Quality

satellite image of Gulf of Alaska
Clear skies over SW Alaska and extensive fog over the Gulf of Alaska captured in a satellite image taken September 13, 2010. Photo: NASA/GSFC, Rapid Response

Resource Briefs Climate at Katmai, 2016.
Climate at Kenai Fjords, 2016.
Climate at Lake Clark, 2016.

Guide to Accessing SWAN Weather Data

Seasonal Weather Summaries

Monitoring Reports


Protocol Documents

SWAN Weather Data by Water Year (Oct.-Sept.)

SWAN Weather at a Glance

Partner Links & Data Access

Subject YouTube Videos

Flickr Photo Galleries

Panoramic Photo Links


Climate is considered the most important broad-scale factor influencing ecosystems. 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 SWAN park units 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.

Monitoring Objectives

  • Record and archive hourly weather observation, including temperature, relative humidity, precipitation, wind speed and direction, solar radiation, and snow depth at weather stations located in representative areas within SWAN parks.
  • Produce monthly and annual summaries of weather observations and identify extremes of climatic conditions for common parameters (precipitation and air temperature), and other parameters for which sufficient data are available (e.g. wind speed and direction, solar radiation, soil temperature).


In general, Alaska has a sparse distribution of weather stations and climate monitoring sites with the majority of these stations located outside parks at low elevation areas of human habitation. Since 2004, SWAN has installed 10 remote automated weather stations in Katmai, Kenai Fjords, and Lake Clark. The site selection process for identifying new locations for these stations was multifaceted and considered exposure, representativeness, elevation, logistics and practical factors, and potential impacts. These criteria were chosen with the designed intent of: maximizing regional climate exposure while minimizing local influences; representing basic climatic averages identified by climate models for a variety of ecoregions; offsetting the low elevation bias of existing weather stations and climate monitoring programs; providing for ease of access (which is critical for the long-term success of a climate monitoring program); and minimizing potential environmental impacts.

Station Design

Weather stations are fully automated and are powered by solar panels. Data is transmitted hourly to a weather satellite and is available in near real-time on the internet. Weather observations include air temperature, wind speed and direction (at 6 m), rainfall, snow depth, relative humidity, and solar radiation.

annotated weather station Kenai Fjords
Weather station near Coville Lake, Katmai. Sensors and components include: 1) wind direction, 2) wind speed, 3) satellite antenna, 4) pyranometer (solar radiation), 5) air temperature and relative humidity, 6) GPS antenna, 7) solar panel, 8) data logger and batteries, 9) rain gauge, and 10) snow depth.
illustrated map of mean annual temperature in southwest Alaska
Mean annual temperature for southwest Alaska. Map was derived from the Parameter-Elevation Regressions on Slopes Model (PRISM) for the base period 1971-2000. The PRISM model uses point climate station data and a digital elevation model to generate gridded interpolations of temperature and precipitation.
illustrated map of mean annual precipitation in southwest Alaska
Mean annual precipitation for southwest Alaska. Map was derived from the Parameter-Elevation Regressions on Slopes Model (PRISM) for the base period 1971-2000.
sky with clouds
Sky with clouds

Resource Brief — Air Quality, 2016

Partner Links & Data Access

Protocol Documents

Air Quality: Visibility and Particulate Matter

Air Quality Inventory and related assessment are being overseen by the NPS, Air Resources Division. The NPS air quality monitoring program has three primary components: visibility, atmospheric deposition, and gaseous pollutant monitoring. In addition, meteorological monitoring is conducted at many locations to aid in the interpretation of measured air pollution levels.

The NPS Air Resources Division does its air quality monitoring in cooperation with other agencies. Whenever possible data is submitted to national archives, such as the EPA AIRS database. Summaries and interpretation of the NPS air quality are best obtained from published reports or data summary reports. In many cases the coordinating organization is the best source for packaged data files, summary maps, and tables.

The Southwest Alaska Network is close to the Tuxedni Wilderness Area, where US Fish and Wildlife are monitoring the Air Quality.

Last Updated: June 30, 2017 Contact Webmaster