Climate and Climate Change Of the American West Coast

Intro Distance along shore from northern WA to southern CA border ~ 1,300 mi. Alaska, Washington, Oregon, California -The western U.S. coastline along the Pacific totals 39,246 mi (NOAA)

Classifying West Coast Climates Koeppen System What is it? A climatic classification scheme based on 2 key meteorological variables: Temperature Precipitation

Mediterranean Climates Distinct summer dry season Clear skies and high temps. Concentration of precipitation in the winter Frequent fogs where cold offshore currents prevail

Mediterranean Climates 30 - 45 degrees N and S of equator Southern CA to central CA Also found in places like Greece

Marine West Coast Climates Both summers and winters are typically mild Few extremes in temperature Frequent drizzle or light rain throughout a year Fog common High winds in the winter

Marine West Coast Climates Northern CA up to WA and Alaskan coast 35 - 60 degrees N and S of equator Dominated by coniferous forest Cover less than 2% of the planet

Wind and Ocean Currents http://www.eschooltoday.com/winds/images/global-atmospheric-circulation.jpg http://blue.utb.edu/paullgj/geog3333/lectures/physgeog.html

Precipitation on the Coast Northern half of coast receives substantial rainfall. Southern half receives much less. Topography inland creates substantial rain shadow effect. Decreased precipitation on eastern side of mountain ranges. http://www-das.uwyo.edu/~geerts/cwx/notes/chap10/westus_precip.gif https://birrell.org/andrew/reliefMaps/image.php?zone=west&type=jpg&scale=25

West Coast Climate Change Sea Level Rise

NOAA Temperature Data Slight increase in summer temperatures. Slight decreases in some winter temperatures in Seattle and Palmdale.

NOAA Precipitation Data

Drought and Stream Flow Reduction With higher temperatures and reduced precipitation during the summer months a change in streamflow timing has been observed from 1948-2008 contributing significantly to a decrease in water availability Decrease in water Flow makes it difficult for human and natural demand for water in the region to be met Decline of Trout Population Suitable habitat projected to decline by 47% by 2020 https://nca2014.globalchange.gov/report/regions/northwest

Tree Disease and Increase in Wildfires Wildfires are a natural part of most Northwest forest ecosystems Warmer temperatures extend suitable Mountain Pine Beetle habitat Opening pines to disease and increasing the possibility of a fire breaking out Warmer summer conditions and tree disease have contributed to the increase in wildfires in the region since 1970 https://nca2014.globalchange.gov/report/regions/northwest

Climate Change & Wildfires

Sources NOAA https://www.climatestotravel.com/climate/united-states-west https://journals.ametsoc.org/doi/full/10.1175/2009JCLI2470.1 http://onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2004.00492.x/pdf https://journals.ametsoc.org/doi/pdf/10.1175/2010JAMC2423.1 http://www-das.uwyo.edu/~geerts/cwx/notes/chap10/westus_precip.gif https://birrell.org/andrew/reliefMaps/image.php?zone=west&type=jpg&scale=25 https://upload.wikimedia.org/wikipedia/commons/9/9b/Corrientes-oceanicas.png http://www.eschooltoday.com/winds/images/global-atmospheric-circulation.jpg https://nca2014.globalchange.gov/report/regions/northwest