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Dec
17

Our changing climate

Learn more about how climate change is impacting King County and the importance of climate action now.

King County is already experiencing the impacts of climate change

Our climate is changing. Climate change will harm people and communities differently across King County based on:

  • Age
  • Gender
  • Health
  • Where they live
  • What they do for work

Rising greenhouse gas emissions will only accelerate these impacts and other changes in the coming decades. affecting the environment, communities and public health, and the economy and infrastructure.

These changes are already affecting our:

  • Environment
  • Communities and public health
  • Economy and infrastructure

Increased heat

Since 1900, average annual air temperature in the Puget Sound region has increased by 1.3 degrees Fahrenheit. It's projected to be 5.5°F warmer in the 2050s.

  • 2015 was the hottest year on record for Washington state
  • Summer of 2017was the hottest and driest record for Seattle

Long-term declines of snow and ice

  • In 2015 there was a record low snowpack (4% of the average amount) in the Central Cascades. This meant less water for people, agriculture, and fish. 

More heavy rain events, and more frequent coastal flooding

  • In January 2015 warm storms brought torrential rain and flooding.
  • Winter 2017 was the wettest winter on record. This created flooding and landslide hazards throughout the Puget Sound region.
  • By the 2080s, our heaviest rain events are expected to be 22% heavier.

Rising sea levels, extreme river conditions, and ocean acidification

  • Our sea levels rose 9 inches from 1899 to 2016. They are expected rise another 15 inches (to 24 inches from 1899) by 2100.
  • We will continue to experience:
    • Lower river flows and warmer water in summers
    • Higher river flows and flooding in fall and winter
  • Ocean chemistry is changing in ways that are harmful to marine species. Increased ocean acidification increases costs to shellfish growers.

Increased wildfire threats

  • Summer 2017 Northwest forest fires created unprecedented summer air quality problems in the Puget Sound region.
  • This poorer air quality increases the rates of illnesses, hospitalizations, and deaths
  • We project a 4-fold increase in annual area burned in Washington's forests by the 2040s.

If we don't act now, the costs and consequences will only grow

The choices we make today will affect the severity of future impacts. We must act now to mitigate harm to:

  • Our environment
    • Increasing stress for salmon.
    • Impacts on forests from insects, disease and fire.
    • Changes in habitat important to local species
    • More harmful algal blooms in lakes and Puget Sound.

  • Our economy
    •  Greater risks to homes, businesses, and infrastructure from increased coastal and river flooding. 
    • Marine-based economies suffer as fish and shellfish diminish.
    • Increased summer drought stress

  • Community public health
    • Negative health impacts from heat exposure.
    • Changes in illnesses carried by ticks and mosquitos.
    • Marine-based economies suffer as fish and shellfish diminish.
    • Increased risks for people with asthma and heart illness due to more summer air pollution.
    • Greater risk of injury and property damage from more extreme weather events.
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