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Is it all Hot Air?Climate Change, Global Warming
& The Pacific Northwest
Climate Change Outreach ProjectPresentation given in Roseburg, Oregon
May 2006
Institute for Natural ResourcesOregon State University
Purpose of this Talk
Provide relevant and reliable science-based information about climate change, its causes and its impacts on the Pacific Northwest
Source: Climate Impacts Group, University of Washington
Reliable and Relevant Information
To make up our own minds about whether or not climate change & global warming is real…
…and if it is real, to decide whether or not it matters to me…
…and if it does matter to me, to help decide what to do about it as an individual, as a community, as a State and as a nation.
Reliable Information
Unbiased source
Uses references so we can determine
• Quality
• Timeliness
Relevant Information
Relates to people’s personal or their families wealth, health and happiness
Hierarchical from local, to regional to national to international
Shared concern about:
• Disadvantaged people
• Charismatic wildlife and ecosystems (rainforest, tundra, coral reefs) as indicators of ecosystem health
The Climate Change Story Covers:
• Trends
• Causes
• Predictions
• Impacts
Trends
Global Climate Change Over the Last 100 Yrs
The earths surface has warmed 1.1°F since 1900
Source: US National Climate Data Center 2001
Source: IPCC 2001
Persistent changes in global rainfall patterns
Alternate Views on Trends
Antarctic Sea Ice Area Anomalies, 1978-2005, from NSIDC (2006)
Arctic air temperatures are no higher now than they were in the 1930s and 1940s
Antarctic sea ice has increased in extent from 1978 to 2005
Alternate Views on Trends
Regional Temperatures haven’t gone up everywhere
Source: Taylor 2006
Reconciling Differences
Differences in trends and their interpretation can only be reconciled through debate and synthesis within the science community
Excerpts:
PNW Climate Change Over the Last 100 Yrs
Rainfall increases in eastern Washington & southern BC
Region wide warming of about 1.1°F in 100 years
Global Climate Change over 1000s of Yrs
Global climate has varied over 100,000s and 10,000s of years
Change in last 100 yrs is not unusual in history of Earth’s climate
Change in last 100 yrs is dramatic compared to climate record in last 1,000 years
Source: Climate Impacts Group, University of WashingtonSource: Alley 2004
Causes
Changes in Emissions and Global Temperature
Since 1750 atmospheric CO2 has increased 34%
In the last 100 years global temperature has increased 1.1°F
Source: Climate Impacts Group, University of Washington
Source: Climate Impacts Group, University of Washington
Are We Causing Global Warming?
Only once human sourced CO2 is added in can we explain observed changes in global temperature
Barnett et al 2005
Modeling of air temperature and sea temperature shows that observed increases in temperature cannot be explained by natural influences alone
Source: IPCC 2001
Source: IPCC 2001
Global Predictions
Global Warming in the 21st Century
Projections of future greenhouse gas concentrations are highly uncertain and this makes precise prediction of global warming difficult
The projected increase in global average temperature by 2100, relative to 1990, ranges from 2.5 to 10° F
We do know the 21st century will be warmer
Source: IPCC 2001
Does This Extra Heat Matter?
Heat drives this circulation. More or less heat changes global ocean and atmospheric circulation affecting regional climates including the Pacific Northwest
Currents in the Earth’s oceans and atmosphere take heat from the tropics to the poles
Without this circulation the tropics would be much hotter and poles much colder
Source: IPCC 2001
Extra Heat and Hurricanes: Is there a link?No evidence of link between global warming and the frequency of hurricanes
Hurricanes act as giant egg beaters mixing warm surface water with deeper cold water
Relationship between sea temperature and the intensity (15% increase wind speed) and duration (60% increase in life time) of hurricanes since 1970
Total Power Dissipated by North Atlantic Hurricanes
Source: Emanuel 2005
Global Sea Level Rise
Source: IPCC 2001
Models predict varying degrees of sea level rise through thermal expansion of the oceans and eventually melt water
Local sea level rise will vary due to the influence to local factors such as tectonic uplift and prevailing ocean conditions
PNW Predictions
Climate Influences on the PNW: Topography
Climate Influences on the PNW: OceanEl Niño/ Southern Oscillation
Warm phase PDO winters tend to be warmer and drier than average. Cool phase PDO winters tend to be cooler and wetter than average
El Niño winters tend to be warmer and drier than average. La Niña winters tend to be cooler and wetter than average
El Nino/ Southern Oscillation
Source: Climate Impacts Group, University of Washington
Pacific Decadal Oscillation
21st Century Changes in PNW Temperature
All climate models project that PNW temperatures will increase
The projected increases exceed the year to year variability experienced during the 20th century
Comparison of Temp Variability
Source: Climate Impacts Group, University of Washington
Source: Climate Impacts Group, University of Washington
21st Century Changes in PNW Precipitation
Many climate models project a slight increase in precipitation especially during winter months
Natural year-to-year and decade-to-decade fluctuations in precipitation are likely to be more pronounced than longer term trends associated with global warming
Comparison of Precipitation Variability
Source: Climate Impacts Group, University of Washington
Source: Climate Impacts Group, University of Washington
2001 & 2005 Predictions of PNW ClimateIn 2005 new & more sophisticated global climate change models were released
The University of Washington used the new models to look at PNW climate predictions
The new models show smaller temperature increases and drier 2020 precipitation projections
The new models show greater warming in summer than in winter
The old models showed more winter than summer warming
Source: Climate Impacts Group, University of Washington
PNW Impacts
Scientific Consensus on Impacts on the PNW from Global Warming
• Negative impacts on PNW water resources including reduction in snowpack
• Negative impacts on endangered salmon
• Impacts on east-side forests with slower growth and more fires from warmer summers
• Loss of some local populations of wildlife and plants if climate shifts are faster than ability to migrate
• Increased beach erosion and beach loss along the Northern Oregon Coast
Source: Climate Impacts Group, University of Washington
Source: Climate Impacts Group, University of Washington
Climate Impacts: PNW Water Resources
Less winter snow accumulation
Higher winter stream flows
Earlier spring snowmelt
Earlier peak spring stream flow
Lower summer stream flows
Warmer 21st century temperatures mean:
Source: Climate Impacts Group, University of Washington
Predicted Columbia River Flows in 2040
Water Resource Case I: Water Allocation Conflicts
Earlier peak river flows, lower summer streamflows, and lengthened summer low flow will heighten competition over water use for:
• Hydropower generation
• Instream flow protection for endangered species
• Irrigation
• RecreationSource: Climate Impacts Group, University of Washington
Source: Climate Impacts Group, University of Washington
Water Resource Case II: SalmonChanges in annual patterns of stream flow will be detrimental to salmon rearing, migration and spawning in some transient river systems
Increased water temperatures in summer may exceed the tolerable limits for trout and salmon
Endangered Species Act implications for power generation & irrigation through higher in-stream flow standards
Water Resource Case III: Snow Pack and SkiingWarmer winter temperatures mean later opening dates, shorter seasons and more rainy days for ski areas below 5,000‘
Latest climate models suggest the worst impacts could be seen later than previously thought
Source: Nolan 2006
At Risk Snow and Ski Areas
Source: Nolan 2006
Sea Level Rise and Coastal ErosionSource: IPCC 2001
Fishing Rock Oregon Coast Source: Sea Grant
Predicted sea level rise will increase coastal erosion hazards along the northern Oregon Coast
This hazard is most severe occur during El Niño events when local sea level is higher
Adapting to Climate Change in the PNW
• Recognize the past is not a reliable guide to the future
• Integrate climate change considerations into planning processes including honest appraisal of current policies in light of climate change
• Monitor regional climate and resources for medium and long-term change
• Expect the unexpected and plan to be adaptable
Mitigating Climate Change in the PNW
• Adopt mitigation strategies that make economic sense as well as environmental sense:
• Green energy generation initiatives
• Fuel and energy efficiency
• Water resource conservation measures
Summary• Climate change is happening globally & in the PNW
• Humans are contributing to global warming and climate change in a measurable way
• The quickest & greatest impact in the PNW will be on water resources due to more rain and less snow at lower elevations
• These water resource impacts will cause increased conflict over water for irrigation, instream flows and electricity generation
• IF we exercise foresight now through sound planning and use of readily available technology, the PNW is well placed to deal with global warming & climate change
• Other parts of the USA, the world and its ecosystems may not be so fortunate
Greenhouse Gas Reduction StrategiesGreenhouse Gas Reduction StrategiesMeasures either (a) save energy costs up front, or (b) are investments Measures either (a) save energy costs up front, or (b) are investments with both economic and environmental returns. They can also create with both economic and environmental returns. They can also create
product/service sales opportunities for Oregon companiesproduct/service sales opportunities for Oregon companies
• Energy efficiency in vehicles, buildings, equipment• More efficient materials, packaging, land uses• Replace fossil fuel generation with wind, solar,
biomass• Replace gasoline/diesel with biofuels• Increase biological sequestration (farm and forest
carbon capture storage)
Source: Governor’s Advisory Task Force on Global Warming
Global Warming Adaptation StrategiesGlobal Warming Adaptation StrategiesFundamentals of ”adaptation”: (1) Net costs with no positive returns; (2) Fundamentals of ”adaptation”: (1) Net costs with no positive returns; (2) costs costs keep going upkeep going up so long as greenhouse gas emissions from fossil so long as greenhouse gas emissions from fossil
fuels are not arrested and reversed. There is no leveling off point.fuels are not arrested and reversed. There is no leveling off point.
• Storms/floods: levees, seawalls, residential/business and infrastructure (highways) relocation, higher-capacity storm-water overflow management facilities
• Public health: insect control, tropical disease treatments, more efficient home/business air conditioning, more “air-quality alert” days possible driving restrictions
• Agriculture: Shift to warm climate crops needing less summer moisture
• Forests: Fuels reduction projects, fire-fighting, less public access, shift to new, small-diameter tree species for forest products
• Energy: New summer electric generation needed to replace lost summer hydro, and to meet growing a/c loads
• Recreation: Shortened ski seasons, possible restricted forest access for hiking/hunting due to increased fire risk
1. Does climate change matter? (How much does climate change matter?)
2. Why do you feel that way? (What is it about climate change that you think is important? What effects or information led you to feel that way?)
3. What do you think we should be doing about climate change, if anything?
Three Questions
• We have the most confidence about the impact of global warming on the PNW’s water resources
• These impacts are generally negative and are the largest of any of the climate change impacts
Climate Impacts in the PNW from Global Warming
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