OUR CHANGING CLIMATE AND ITS IMPACTSAn overview of climate change, climate impacts, and why it matters

Lara Whitely BinderLara Whitely BinderUW Climate Impacts GroupUW Climate Impacts Group

ITEP Tribal Air Quality ConferenceITEP Tribal Air Quality ConferenceJune 16, 2011June 16, 2011

Climate science in the public interest

Key Points to Today’s Talk

• Human activities are altering and will continue to alter 21st century climate. How we experience climate change is a function of natural variability and climate change.

• Effects of a changing climate are already apparent, although also reflective of natural variability.

• Projected “high confidence” impacts include increasing temperatures, sea level rise, ocean acidification, declining snowpack, and shifts in streamflow patterns and timing.

• Information exists now for preparing for climate change impacts.

What is Driving Present Day Climate Change?

The current concentrations of key greenhouse gases, and their rates of change, are unprecedented in the

last 10,000 years.

Carbon dioxide (CO2) Methane (CH4) Nitrous Oxide (N2O)

+ 35% + 18%+ 142%

Current concentrations are higher than any time in at least the past ~780,000 years

~70% of CO2 emissions come from fossil fuel burning (chemical “fingerprint”)

2010 avg annual CO2

concentration: 389 ppmv

From a long term perspective, these changes are enormous

Longer-term CO2 Trends2010

Average global temperature has increased 1.3°F since 1906.

Warming since the 1950s very likely (>90% probability) due to the observed increase in GHG from human activities.

Figure source: IPCC 2007

Recent U.S. Temperature Trends

Average annual temperature in most areas of the U.S. have warmed 1 to 2°F since 1961.

High-humidity heat waves (key char: high nighttime temps) have increased in the last 3 to 4 decades.

Source: USGCRP 2009

Average annual temperature increased +1.5F in the PNW during the 20th century

3.6 °F

2.7 °F

1.8 °F

0.9 °F

Cooler Warmer

Mote 2003(a), updated

Temperature Trends (°F per century), since 1920

20th Century PNW Temperature Trends

• Much of the warming took place after 1950

• Most of the warming has occurred in winter and spring

• An estimated 1/3 of warming attributable to ENSO and PDO

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Arctic sea ice extent has declined Arctic sea ice extent has declined (-34%, 1979-2009)(-34%, 1979-2009) (NASA 2009a)(NASA 2009a)

• Mean thickness has declined Mean thickness has declined (- 23% , 1987-2007)(- 23% , 1987-2007) (NASA 2009b)(NASA 2009b)

• Seasonal ice is now the dominant ice type Seasonal ice is now the dominant ice type (Kwok et al. 2009)(Kwok et al. 2009)

• The Arctic sea ice melt season has The Arctic sea ice melt season has lengthened lengthened (20 days longer on average, 1979-2007)(20 days longer on average, 1979-2007) (Markus et al. 2009)(Markus et al. 2009)

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• The growing season in the The growing season in the U.S. and Canada has U.S. and Canada has increased increased (+2 days/decade on average (+2 days/decade on average since 1950) since 1950) (IPCC 2007, WG2)(IPCC 2007, WG2)

• Primary driver: earlier onset of Primary driver: earlier onset of spring spring (IPCC 2007, WG2; Linderholm et al 2006)(IPCC 2007, WG2; Linderholm et al 2006)

• Changes in growing season Changes in growing season length vary by region, altitude, length vary by region, altitude, and latitude and latitude (Linderholm et al 2006)(Linderholm et al 2006)

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Northern Northern hemisphere hemisphere spring snow cover spring snow cover has declined has declined (~8%, 1922-2005) (~8%, 1922-2005) (Lemke et al., 2007)(Lemke et al., 2007)

• Western U.S. Western U.S. spring snowpack spring snowpack has declined has declined (decreased in 73% (decreased in 73% (n=824)(n=824)of stations, of stations, 1950-1997) 1950-1997) (Mote et al. (Mote et al. 2005)2005)

Decrease Increase

Mote et al. 2005

Over the past 1,000 yrs, late 20th-century (1980s to present) snowpack reductions are

almost unprecedented in magnitude across the northern Rocky Mountains

Pederson et al. 2011

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Northern hemisphere spring snow cover has declined (~8%, 1922-2005) (Lemke et al., 2007)

• Western U.S. spring snowpack has declined (decreases in 73% (n=824)of stations, 1950-1997) (Mote et al. 2005)

• Spring snowmelt Spring snowmelt and peak runoff and peak runoff have shifted have shifted earlier earlier (1 to 4 weeks in (1 to 4 weeks in much of the western much of the western U.S., 1948-2002) U.S., 1948-2002) (Stewart et al. 2005)(Stewart et al. 2005)

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Northern hemisphere spring snow cover has declined (~8%, 1922-2005) (Lemke et al., 2007)

• Spring snowpack has declined (decreases in 73% (n=824)of western U.S. stations, 1950-1997) (Mote et al. 2005)

• Spring snowmelt and peak runoff have shifted earlier (1 to 4 weeks in much of the western U.S., 1948-2002) (Stewart et al. 2005)

• Northern Northern hemisphere hemisphere glaciers are glaciers are losing mass losing mass and/or length.and/or length.

South Cascade Glacier

Mount Baker-Snoqualmie National Mount Baker-Snoqualmie National ForestForest

Photos courtesy of Dr. Ed Josberger, USGS Glacier Group, Tacoma, WA

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Ocean pH has decreased Ocean pH has decreased 30%30% (drop of ~0.1 since ~1750)(drop of ~0.1 since ~1750)(Feely et al. 2008)(Feely et al. 2008)

• Some of the strongest areas Some of the strongest areas of acidification are in of acidification are in upwelling zones along the U.S. upwelling zones along the U.S. west coastwest coast (Feely et al. 2008)(Feely et al. 2008)

Evidence of change is increasingly visible throughout Earth’s natural systems

Observed 20th century change

• Ranges for algal, plankton, and Ranges for algal, plankton, and fish have shifted poleward in fish have shifted poleward in high-latitude oceans.high-latitude oceans.

• Plant and animal ranges are Plant and animal ranges are shifting northward and to higher shifting northward and to higher elevations.elevations.

IPCC WG2 2007, Janetos et al. 2008IPCC WG2 2007, Janetos et al. 2008

http://www.arborday.org/media/mapchanges.cfm

Changes in USDA Hardiness Zones

PROJECTED CHANGES IN CLIMATE

Climate Modeling, Climate Projections, and Projected National and Regional Change

Projecting Future Climate: Greenhouse Gas Emissions Scenarios

40 emissions scenarios are used to “drive” global climate models.

Different scenarios result in different climate change projections.

Figure source: IPCC 2001, Summary for Policy Makers

Current emissions are in the current range of the A1B scenario.Current emissions are in the current range of the A1B scenario.

A1B

A2

B1

A1B

A2

B1

CO2 Emissions Scenarios CO2 Concentrations

A1FI

A1FI

Figure source: IPCC 2007 WG1, Summary for Policy Makers

IPCC “best estimate” range of global-scale warming by the 2090s:

3.2°F-7.2°F (likely range: 2-11.5°F)

Without drastic changes in current emissions trends, GHG concentrations will increase dramatically over the 21st

century and with that, global temperature.

More warming is expected over land surface and in the Northern Hemisphere

Projected surface temperature changes for the early and late 21st century, relative to 1980 to 1999

Figure source: IPCC 2007 WG1, Technical Summary, Fig TS.28

B1

A1B

A2

End of Century (2080-2099 Average) Projected Temperature Change (°F),

relative to 1961-1979 baseline

Range: +4 to +6.5°F

Higher Emissions Scenario (A2)

USGCRP 2009

Range: +7 to +11°F

Lower Emissions Scenario (B1)

USGCRP 2009

A2 Scenario

Projected Increases in Annual PNW Temperature* Relative to 1970-1999 average

Mote and Salathé, 2009

°F°C

Historic

2020s +2.0°F (1.1-3.4°F)

2040s +3.2°F (1.6-5.2°F)

2080s +5.3°F (2.8-9.7°F)

Projected Change in North American Precipitation, 2080-2099

A2 Scenario

hatching = areas with highest confidence

USGCRP 2009

Historic

Mote and Salathé, 2009

Projected Increases in Annual PNW Precipitation* Relative to 1970-1999 average

2020s +1% (-9 to 12%)

2040s +2% (-11 to +12%)

2080s +4% (-10 to +20%)

USGCRP 2009

Nationally, the 1-in-20 year extreme precip events is expected to be 10 to 25% heavier by the 2090s than present day (specific changes

vary by location).

Increasing Extreme Precipitation

What About Changes in PNW Extreme Precipitation?

Simulations generally indicate increases in extreme precipitation over the next 50 years, however:

– The projections vary by model and region, and

– Actual changes may be difficult to distinguish from natural variability.

Salathé et al. 2009, Rosenberg et al. 2009)

-29% -23%

Chapter 5 - Macro-Scale Hydrologic Model Implementation, Elsner and Hamlet (2010), http://www.hydro.washington.edu/2860/. Map by Rob Norheim, CIG

Key Impact: Reduced Spring Snow Cover

Red shading indicates areas where April 1 snowpack is

expected to decline.

1916-2006

Elsner et al. 2009

Increasing winter flows Earlier, lower

peak runoff

Lower summer streamflow

Runoff patterns are temperature dependent, but the basic response is more runoff and streamflow in winter and early

spring, with less in late spring and early summer

A transient (snow/mix basin)

Impacts to Seasonal Streamflow Timing cont.

Rain and Snowmelt Dominant Basins

Rain Dominant Snowmelt Dominant

Global Projections for 2100:+7 to +23 inches (IPCC 2007)

and more recently

+2.6 ft to +6.6 ft (Pfeffer et al. 2008)

Sea Level is Expected to Increase

Major determinants of global sea level rise:

Jakobshavn Fjord, Greenland

• Melting of land-based ice sheets (Greenland, Antarctica)

• Thermal expansion of the ocean

Sea level will not stabilize until several centuries after global temperatures stabilize.

Washington State Sea Level RiseMedium (w/range) estimates of sea level rise in Washington for 2100:

. .

NW Olympic Peninsula: +2” (-9 to +35”)

Central/Southern Coast:Central/Southern Coast:+11” +11” (+2 to +43”) (+2 to +43”)

Puget Sound: Puget Sound: +13” +13” (+6 to +50”) (+6 to +50”)

Mote et al. 2008

Ocean AcidificationOcean Acidification

• Oceans have absorbed approximately 1/3 of Oceans have absorbed approximately 1/3 of the carbon emissions released by human the carbon emissions released by human activities since the preindustrial era. activities since the preindustrial era.

• As a result, ocean water is becoming more As a result, ocean water is becoming more acidicacidic.

• Projected increase in ocean acidity by 2100: Projected increase in ocean acidity by 2100: 150% (IPCC A2 scenario)150% (IPCC A2 scenario)

Effects of increasing carbon dioxide and temperature on coral reefs

Credit: NOAA Coral Reef Targeted Research and Capacity Building for Management Program

What Can Influence Species Vulnerability?

Functioning at the edge of geographic/elevation rangese.g., alpine meadows

Dependence on specialized habitat and/or microhabitat requirementse.g., Cascades frog (Rana cascadae)

Impacts affecting specific life stages e.g., emergent tree seedlings

Narrow environmental tolerances or thresholdse.g., temperature thresholds for salmon

Source: Snover et al, in review; IUCN 2008; Josh Lawler, UW

Factors Influencing Vulnerability cont’d

Source: Snover et al, in review; IUCN 2008; Josh Lawler, UW

Presence of feedbacks and multiple stressese.g., drought stress and wildfire

Dependence on specific environmental triggers e.g., lodgepole pine

Dependence on interactions between speciese.g., zooplankton, phytoplankton blooms; freshwater mussels (glochidia)

Poor ability to disperse or colonize new rangese.g., corals, Rockfish, Dungeness Crabs

Population growth rates

Clio pyramidata, R. Hopcroft, U of Alaska Fairbanks

NOAAwww.wildnatureimages.com

Dr. Monica G. Turner, UW Madison

• Substantial reduction in area of distribution projected (decreases by 81-98%)

• Increasingly fragmented distribution

Trook and Hicke, in revision Slide courtesy of Jeff Hicke

Climate Change Impacts on Pika Distribution

NWF (2007) evaluation of impacts to coastal habitat at 11 locations in Washington and Oregon from 27.3” of sea level rise:

•65% loss of estuarine beaches•61% loss of tidal swamps•44% loss of tidal flats•52% conversion of brackish marsh to tidal flats, transitional marsh, and saltmarsh

Loss could affect availability of this habitat for spawning, juvenile rearing, migratory and over-wintering stopovers, commercial shellfish production

Impacts to PNW Coastal Habitats

National Wildlife Federation (2007), Sea-level Rise and Coastal Habitats in the Pacific Northwest

An Analysis for Puget Sound, Southwestern Washington, and Northwestern Oregon

Floods

Warm, lowstreamflow

Salmon Impacted Across Full Life-Cycle

Acidification, warming, winds?

Warmer lower

flows in summe

r

Modified from Wilderness Society (1993)

Changes in Species DistributionProjected suitability changes: Lodgepole pine

Littell et al. 2009

Data: Rehfeldt et al. 2006; Map by Rob Norheim, UW CIG

Littell et al. 2009Data

: Reh

feld

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l. 20

06; m

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*Modeled current distribution

*

Changes in Species DistributionProjected suitability changes: Douglas-fir (2060s)

The amount of area burned throughout the West is projected to increase.

Fig

ure

sour

ce: J

erem

y Li

ttell,

CIG

. Map

by

Rob

Nor

heim

, UW

CIG

Risk of Forest Fire Increases

For the PNW as a whole, probability of a year >> 2 million acres increases:

• Historical: 5%• 2020s: 5% (1 in 20)• 2040s: 17% (~1 in

6)• 2080s: 47% (~1 in

2) Littell et al. 2009

Projected change (%) in area burned by ecoprovince for 1°C increase in average global temperature.

Human Health – Washington State

• In Washington, climate change will lead to larger numbers of heat-related deaths due mainly to hotter summers. For example in greater Seattle, a medium climate change scenario projects 101 additional deaths for people over 45 by 2025 and another 50% increase by 2045

• Although better control of air pollution has led to improvements in air quality, warmer temperatures threaten some of the sizeable gains that have been made in recent years.

Jackson et al. 2009

Information Sources • ITEP

• University-based research programs (e.g., CIG, NOAA Regional Integrated Sciences and Assessment programs [RISAs])

• Federal agencies:

– US EPA

– USGS Climate Science Centers

– Landscape Conservation Cooperatives

• National Research Council’s “America’s Climate Choices” report series, specifically “Advancing the Science of Climate Change”

• US Global Change Research Program – “Global Climate Change Impacts in the U.S.” report (2009) + 2nd Nat’l Assess. (2012?)

• Intergovernmental Panel on Climate Change (2007 report)

F

For questions, please contact

Lara Whitely Binder

Climate Impacts Group

University of Washington

lwb123@uw.edu