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Climate change reports and publications

We use research from the University of Washington's Climate Impacts Group to guide policy decisions related to climate change. We also conduct our own long-term monitoring of marine waters and collect marine data.

Water rushing through the Bonneville Dam in Washington state.

Bonneville Dam

Preparing for a Changing Climate

According to our report, Preparing for a Changing Climate, rising levels of carbon dioxide and other heat-trapping gases in the atmosphere have warmed the Earth and are causing wide-ranging impacts, including:

  • Water supply impacts
  • More extreme heat events and droughts
  • Rising sea levels
  • More extreme storms, rainfall, and floods
  • Impacts to infrastructure

Scientists project that these trends will continue and in some cases accelerate, posing significant risks to human health, forests, agriculture, freshwater supplies, coastlines, and other natural resources that are vital to Washington state’s economy, environment, and quality of life.

Washington Greenhouse Gas Emission Reduction Limits

The Washington Legislature recognized the need to act on climate change and the severity of its threat to Washington and in 2008 established limits on the state’s greenhouse gas (GHG) emissions. We are required to review these limits and make recommendations regarding revisions using science from the University of Washington’s Climate Impacts Group.

Ecology’s latest recommendations are available in the Washington Greenhouse Gas Emission Reduction Limits report that was provided to the state Legislature in December. 2016. These recommendations included increasing the level of GHG reductions by 2035, and by 2050.

Existing state greenhouse gas limits:

  • By 2020, reduce overall emissions of greenhouse gases in the state to 1990 levels.
  • By 2035, reduce overall emissions of greenhouse gases in the state to 25 percent below 1990 levels.
  • By 2050, the state will do its part to reach global climate stabilization levels by reducing overall emissions to 50 percent below 1990 levels, or 70 percent below the state's expected emissions that year.

Recommended limits:

  • By 2020, reduce overall emissions of greenhouse gases in the State to 1990 levels.
  • By 2035, reduce overall greenhouse gas emissions in the state to 40 percent below 1990 levels.
  • By 2050, reduce overall greenhouse gas emissions in the state to 80 percent below 1990 levels.

Climate change in Puget Sound

A new report from the Climate Impacts Group, State of Knowledge: Climate Change in Puget Sound, provides a comprehensive synthesis of relevant research on the likely effects of climate change on the Puget Sound region.

Projected changes include:

  • Average air temperatures in Puget Sound will rise by between 2.9 and 5.4 degrees Fahrenheit by the 2050s, for the most optimistic scenario of future greenhouse gas emissions.
  • Ocean levels will rise by 4 to 56 inches by 2100, with the latest predictions offering more specifics on geographic variability and the effects of storm surges.
  • Increasing acidity of seawater will affect the shellfish industry, and may increase the toxicity of some algal blooms. Impacts on other marine life are not yet fully known.
  • Winter flooding will increase due to rising oceans, more winter precipitation falling as rain rather than snow, and more frequent and intense heavy rains.

Climate change impacts on groundwater

In March 2016, we released a report on the Predicted Impacts of Climate Change on Groundwater Resources of Washington State. This report summarizes findings from an evaluation of how global climate change may impact groundwater resources in Washington in the coming decades.

Although typically out of sight, groundwater is a highly valuable natural resource for Washington’s citizens, economy, and environment. Throughout the state, groundwater provides a major source of water supply, sustains streamflows and wetland functions during biologically critical periods of the year, and helps to buffer the impact of short-term droughts.

Global-scale climate changes are unfolding at rapid rates in comparison to historical patterns, and are expected to have far-reaching consequences for Washington’s water resources.

Washington's state of knowledge report

The State of Knowledge Report: Climate Change Impacts and Adaptation in Washington State: Technical Summaries for Decision Makers, summarizes existing knowledge about the likely effects of climate change on Washington and the Pacific Northwest, with an emphasis on research since 2007.

This report provides technical summaries detailing observed and projected changes for Washington’s climate, water resources, forests, species and ecosystems, coasts and ocean, infrastructure, agriculture, and human health in an easy-to-read summary format designed to complement the foundational literature from which it draws. The report also describes climate change adaptation activities underway across the state and data resources available to support local adaptation efforts.