Transcript IPCC

Slides for Communicating IPCC
IPCC Working Group II
Summary For
Policymakers: Impacts,
Adaptation and
Vulnerability
April 6, 2007
www.ucsusa.org
Figure: Courtesy of IPCC
Working Group II:
174 Lead Authors
222 Contributing Authors
45 Review Editors
Full Report 1,572 pages
Summary for Policymakers
Overview:
Consequences on the Ground
Water
Food
Species
Coasts
Extreme Events
Health
What the IPCC Means by “high confidence”
The IPCC uses specific language, also indicated by
number of asterisks, to describe confidence
regarding statements:
•very high confidence*** (9 out of 10 chance),
•high confidence** (8 out of 10 chance),
•medium confidence* (5 out of 10 chance).
Human-induced climate change
Observational evidence from all continents and
most oceans shows that many natural systems are
being affected by regional climate changes,
particularly temperature increases.
•89% of the 29,000 datasets that IPCC examined
exhibited changes in the direction expected from
warming.
Human-induced climate change
It is likely that since 1970, human-induced warming
has had a discernible influence on many physical
and biological systems.
WATER
•Hundreds of millions of people will be exposed to
increased water stress, which will get worse with
increasing temperatures.**
•Water availability will decrease by as much as 30%
in current drought-prone areas, in the dry tropics,
and over much of the mid-latitudes, including the
southwestern U.S.**
WATER
•The more than one sixth of the world population
that currently lives near rivers that derive their water
from glaciers and snow cover will see their water
resources decline.**
•Water resources will be diminished in western
North America as decreased snowpack in the
mountains reduces summer river flows.***
FOOD
•Hunger risk is projected to increase for low latitude
regions, in particular the seasonally dry tropics, as
these areas will likely experience decreased crop
yields for even small temperature increases.
•Regions in Africa will be particularly prone to
hunger risk due to a reduction in the areas suitable
for agriculture.**
FOOD
•Under slight temperature increases, higher latitude
regions such as Northern Europe, North America,
New Zealand, and temperate zone soybean regions
of Latin America can adapt and benefit from
increased growing season length, more
precipitation, and/or less frost.
•However, if local mean average temperature rise
exceeds 5.0 degrees Fahrenheit (2.8 degrees
Celsius), crop yields in some regions are projected
to decline in mid to high latitudes.*
SPECIES
•Species have already shifted their ranges to higher
latitudes and higher elevations over the past several
decades.***
•Twenty to thirty percent of assessed plant and
animal species on Earth will face extinction if the
increase in global average temperature exceeds
2.3-4.1ºF (1.3-2.3ºC).*
SPECIES
•The capacity of many species and ecosystems to
adapt will be exceeded in this century as climate
change and its associated disturbances (including
floods, drought, wildfire, insects, and ocean
acidification) increase.**
•If sea surface temperature increases above
seasonal average maximum level by around 1.8
degrees Fahrenheit (1 degree Celsius) coral
bleaching of most corals occurs and above 3.6
degrees Fahrenheit (2 degrees Celsius) most corals
die.**
COASTS
•Many millions more people are projected to be
flooded every year due to sea-level rise by the
2080s.***
•The most vulnerable populations are the largest
mega-deltas of Asia and Africa and small islands.***
Extreme Events
•Where extreme weather events such as heat
waves, droughts, fires, wildfires, floods, and severe
storms become more intense an/or frequent, the
economic and social costs of those events will
increase. **
•Disturbances from pests, diseases, and fire are
projected to have increasing impacts on U.S.
forests, with an extended fire season and large
increases in area burned. ***
Human Health
•Projected climate change-related exposures will
affect the health status of millions of people
worldwide.
•U.S. cities that currently experience heat waves are
expected to be challenged with an increased
number, intensity, and duration of heat waves over
the course of the century, with potential for negative
health impacts. ***
Human Health
•Some infectious diseases, such as those carried by
insects and rodents, may become a growing
problem. **
•The elderly, the children, and the poor of all nations
are the most vulnerable populations and may be
unable to cope with the climate change stresses.
THANK YOU!
WG2 SPM
General Regional
Impacts
To
California specifics
IPCC, 2007 – North America
“"Warming in western mountains is
projected to cause decreased snowpack,
more winter flooding, and reduced
summer flows, exacerbating competition
for over-allocated water resources”
IPCC, FAR 2007
North America section
Will California receive adequate
precipitation?
Little consensus wetter or drier
Cayan et al. 2006
Decreasing
Snowpack
Increasing Warming
CA Climate Change Center Summary Report (2006)
“Disturbances from pests, diseases, and fire
are projected to have increasing impacts on
forests, with an extended period of high fire
risk and large increases in area burned.”
IPCC, FAR 2007
North America section
Climate change impacts on forests
• Increased Temperatures
– (effects Productivity)
• CO2 fertilization
– (effects Productivity)
• Longer Dry Season
– Increased vulnerability to:
•
•
•
Widlfires
Pests
Direct mortality
• Shifts in species distribution
Slide modified from Climate Impacts group, Washington
www.cses.washington.edu
Wildfires Frequency increased
four fold in last 30 years.
Western US area burned
Source: Westerling et Al. 2006
Increasing Wildfire Frequency
Increasing Warming
CA Climate Change Center Summary Report (2006)
“Coastal communities and habitats will be
increasingly stressed by climate change
impacts interacting with development and
pollution...”
IPCC, FAR 2007
North America section
WG2 SPM
General Regional
Impacts
To
California specifics
IPCC, 2007 – North America
“"Warming in western mountains is
projected to cause decreased snowpack,
more winter flooding, and reduced
summer flows, exacerbating competition
for over-allocated water resources”
IPCC, FAR 2007
North America section
Will California receive adequate
precipitation?
Little consensus wetter or drier
Cayan et al. 2006
Decreasing
Snowpack
Increasing Warming
CA Climate Change Center Summary Report (2006)
“Disturbances from pests, diseases, and fire
are projected to have increasing impacts on
forests, with an extended period of high fire
risk and large increases in area burned.”
IPCC, FAR 2007
North America section
Climate change impacts on forests
• Increased Temperatures
– (effects Productivity)
• CO2 fertilization
– (effects Productivity)
• Longer Dry Season
– Increased vulnerability to:
•
•
•
Widlfires
Pests
Direct mortality
• Shifts in species distribution
Slide modified from Climate Impacts group, Washington
www.cses.washington.edu
Wildfires Frequency increased
four fold in last 30 years.
Western US area burned
Source: Westerling et Al. 2006
Increasing Wildfire Frequency
Increasing Warming
CA Climate Change Center Summary Report (2006)
“Coastal communities and habitats will be
increasingly stressed by climate change
impacts interacting with development and
pollution...”
IPCC, FAR 2007
North America section