pnw climate change impacts & related studies
DESCRIPTION
PNW Climate Change Impacts & Related Studies. Marketa McGuire Elsner Climate Impacts Group Center for Science in the Earth System Joint Institute for the Study of the Atmosphere and Ocean University of Washington November 28, 2007 Public Meeting of the League of Women Voters. - PowerPoint PPT PresentationTRANSCRIPT
PNW Climate Change Impacts & PNW Climate Change Impacts & Related StudiesRelated Studies
Marketa McGuire Elsner
Climate Impacts GroupCenter for Science in the Earth SystemJoint Institute for the Study of the Atmosphere and OceanUniversity of Washington
November 28, 2007Public Meeting of the League of Women Voters
Climate science in the public interest
Why Climate Change MattersWhy Climate Change Matters
The PNW’s ecosystems, communities, and economy are sensitive to changes in climate.
Global and regional climate is already changing, and these changes are expected to accelerate in the coming decades.
Significant climate change impacts are projected, and the impacts expected in the next few decades are largely unavoidable.
Local governments are on the front line with respect to dealing with climate impacts.
824 snow courses73% – trends
Large – trends PNWSome + trends SW
Trend in Apr 1 Trend in Apr 1 Snowpack Snowpack 1950-20001950-2000
Spring snowpack is projected to decline as more winter precipitation falls as rain rather than snow, especially in warmer mid-elevation basins
Snowpack will melt earlier with warmer spring temperatures
Lower Spring SnowpackLower Spring Snowpack
+4°F, +4.5% winter precip
April 1 Snowpack
0
20
40
60
80
100
120
oct nov dec jan feb mar apr may jun jul aug sep
Sim
ula
ted
Bas
in A
vg R
un
off
(m
m)
1950
plus2c
Simulated Changes in Natural Runoff Timing in the Simulated Changes in Natural Runoff Timing in the Naches River Basin Associated with 2Naches River Basin Associated with 2°°C WarmingC Warming
Impacts:•Increased winter flow•Earlier and reduced peak flows•Reduced summer flow volume•Reduced late summer low flow
Warmer temperatures: More water, less snow in
winter mid- , low elevations Less water in summer
Increased risk of winter flooding in many basins (changes in urban flooding less clear)
Increased risk of summer drought
Negative impacts on hydropower production, irrigation water supply, instream flow protection
More stress on urban water supplies
Impacts on Water ResourcesImpacts on Water Resources
Overall: climate change will require increasingly complex trade-offs between competing management objectives
Washington State Climate Washington State Climate Impacts AssessmentImpacts Assessment
Funding Source: Clean Air/Clean Fuels House Bill 1303
Answers to FAQ regarding HB 1303 from the Washington State Legislature website:http://apps.leg.wa.gov/billinfo/default.aspx
Human Health
Agriculture
SalmonForest Resources
Coast Lines Energy
Infrastructure
Water Resources
A comprehensive state climate change
assessment that includes the impacts of
global warming
Adaptation / Legal Barriers
Hydrologic Scenarios Database for the Hydrologic Scenarios Database for the Columbia River BasinColumbia River Basin
Working in Coordination With Regional Stakeholders
Planning Framework Incorporating Climate Information and Uncertainty
Ecology BPA NPCC State of OR British Columbia (BC Hydro,
Ministry of Environment)
~20 GCMs 2 Emissions Scenarios 2 Downscaling Approaches
Large Scale Planning Studies WRIA Water Supply Planning Specific Planning Studies
• Motivation for writing grew out of October 2005 King County climate change conference
• Written by the CIG and King County, WA in association with ICLEI – Local Governments for Sustainability
• Written to compliment ICLEI’s “Climate Resilient Communities” Program
• Focused on the process (not a sector), and written for a national audience
www.cses.washington.edu/cig/fpt/guidebook.shtml
Why Climate Change MattersWhy Climate Change Matters
Global and regional climate is already changing
These changes are expected to accelerate in the coming decades
Changes in snowpack and streamflow caused by rising temperatures will have important consequences for resources across the Pacific Northwest
Climate Impacts Group strives to provide information and tools to help planning and adaptation
Climate science in the public interest
More information on PNW climate impacts and planning for climate change is
available from
The Climate Impacts Group
www.cses.washington.ed/cig
Marketa McGuire Elsner
Projected range of global-scale warming by the 2090s: 3.2°F-7.2°F
Warming expected through 21st century even if CO2 emissions end today due to persistence of greenhouse gases.
Carbon Dioxide ~60% of warming from GHG 5 to 200 years
Methane ~20% of warming from GHG 8 to 12 years
Nitrous Oxide ~6% of warming from GHG ~120 years
CF4 (Perfluoromethane) >50,000 years
Estimated atmospheric
lifetime of major greenhouse gas
(per molecule)
Data source: IPCC 2001
2121stst Century Global Warming Century Global Warming
Regional Impacts
• Salmon: increased stress from floods, warm streams, low summer streamflows
• Forests: increased risk of wildfire, vulnerability to insects, decreased growth & regeneration
• Coasts: inundation, erosion, habitat loss, flooding
• Agriculture: increased production?, decreased irrigation supply, increased heat stress/insects
• Recreation/Tourism: shortened winter ski season (improved access?), summer impacts from forest fires
• Hydropower: increased winter production, lower summer production
Impacts on Other PNW ResourcesImpacts on Other PNW Resources
Overall: climate change will require increasingly complex trade-offs between competing management objectives