Climate Impacts on the Pacific NorthwestEric SalathClimate Impacts Group (JISAO/SMA) University of WashingtonThe Science of Global Warming:

The Greenhouse Effect

Is Our Climate Changing? The Pacific Northwest113 stations with long recordsAlmost every station shows warmingUrbanization not a major source of warmingwarming cooling100-year Temperature Trends

1,000 Years of Climate Change

150 Years of Climate Change

carbon dioxide concentration has increased by ~30% since 1750s from a very long term perspective, these changes are enormousHumans are altering the atmosphere

Natural Climate InfluenceHuman Climate InfluenceAll Climate InfluencesWhodunit?From IPCC Working Group I

Will Warming Continue?

Future Climate ChangeClimate is changing, and humans are partly responsible. Average surface temperature will probably increase by 3 to 11F (1.5-6.0C) by the year 2100. Other climate changes are likely to accompany this warming (precipitation, storm tracks). These changes will have both positive and negative consequences.

What Might Climate Change Look Like in the Northwest?We looked at 7 scenarios of future climate from climate modelsAverages of 7 scenarios, compared to 20th century:2F warmer by 2020s4F warmer by 2050sSlightly wetterWinters wetterSummers ???

The Main Impact: Less SnowApril 1ColumbiaBasinSnowExtent

Impacts of Hydrologic ChangesLess snow, earlier melt meansMore water in winterLess water in summer

FloodingIrrigationSalmonHydropowerMunicipal waterNatural Columbia River flow at the Dalles, OR.

Are We Prepared for a Changing Climate?Natural resource management presently assumesClimate does not changeBut what if it does?

Becoming ClimatewiseUse climate information Requires on-going dialogue between decision-makers, climate scientists, and the general public

Create centralized & adaptable management strategies

Learn from the past

ConclusionsClimate change likely to significantly affect the pacific northwestMain impact: reduction in snowcap, summer streamflow Will exacerbate existing stresses in many casesNeed to retool institutions and government agencies to respond to climate information and to plan for a changed climateConsider climate a component of any long-term plan

As Ben Franklin put it

The question is, are we...

1. The single most important thing that the region can do to prepare for climate change is to use climate information in our planning and decision-making processes.-- increased awareness of how climate affects the region will enable decision makers to better manage the regions natural resources as the climate changes-- as scientists learn how climate forecasts are used, they can make more useful forecasts and provide more useful information on climate change 2. Management needs to be flexible/agile enough to operate differently under different climate conditions. Much water res mgt based on strict rule curves that define how managers must operate and dont allow them to adapt to conditions that may vary from year-to-year. Following flood prevention rule curves was one of the reasons SPU experienced water shortages in 1992. 3. Climate variations such as El Nino/La Nina and the PDO have been with us throughout this century. By examining how well we dealt with these climate variations in the past, we can prepare for the future. When the SPU learned how EN had impacted them in the past, they used that knowledge and forecasts of EN to help them better prepare for the future.

*Applies to management of nat resources in general as the climate changes

* Now address specific ways to adapt to projected impacts of climate change on water, salmon...

CC: As Phil described, we know from the past that subtle variations in climate can have profound impacts on the region, and the changes projected by the climate models are anything but subtle.

IMPACTS: are likely to be felt among the natural resources of the region -- the water res.

RETOOL: At present, the region is ill-prepared to tackle a changing climate, but some improvements are being made. climate change will also bring some benefits, but we will be most likely to reap those benefits if we are prepared for them.

LONG-TERM: Think about some long-range plans and decisions that are currently being made: habitat conservation plans, salmon recovery plans, plans to ensure future water supply for cities and towns, dam relicensing, land use planning near shore and bluffs and in potential flood areas, and planting of trees for commercial timber. CVs and CC have an important bearing on each of these decisions. We know enough already to begin the process of changing how we think about climate in the context of natural resources decisions.Its time to start.