Phenomena
and direction
of trend |
Likelihood of future
trend based on
projections for 21st
century using SRES
scenarios |
Examples of major projected impacts by sector |
|
|
Agriculture,
forestry and
ecosystems |
Water
resources |
Human
health |
Industry/settlement/
Society |
Warmer and
fewer cold days
and nights;
warmer/more
frequent hot
days and nights
over most land
areas |
Virtually
certain |
Increased yields
in colder
environments;
decreased
yields in warmer
environments;
increased
insect
outbreaks |
Effects on
water resources
relying on snow
melt; increased
evapotranspiration
rates |
Reduced human
mortality from
decreased cold
exposure |
Reduced energy demand
for heating; increased
demand for cooling;
declining air quality in
cities; reduced disruption
to transport due to snow,
ice; effects on winter
tourism |
Warm
spells/heat
waves:
frequency
increases over
most land areas |
Very likely |
Reduced yields
in warmer
regions due to
heat stress; wild
fire danger
increase |
Increased water
demand; water
quality
problems, e.g.,
algal blooms |
Increased risk of
heat-related
mortality,
especially for the
elderly, chronically
sick, very young
and sociallyisolated |
Reduction in quality of life for people in warm
areas without appropriate
housing; impacts on
elderly, very young and
poor. |
Heavy
precipitation
events:
frequency
increases over
most areas |
Very likely |
Damage to
crops; soil
erosion, inability
to cultivate land
due to water
logging of soils |
Adverse effects
on quality of
surface and
groundwater;
contamination
of water supply;
water scarcity
may be relieved |
Increased risk of
deaths, injuries,
infectious,
respiratory and
skin diseases,
post-traumatic
stress disorders |
Disruption of settlements,
commerce, transport and
societies due to flooding;
pressures on urban and
rural infrastructures |
Area affected by
drought:
increases |
Likely |
Land
degradation,
lower yields/crop
damage and
failure; increased
livestock deaths;
increased risk of
wildfire |
More
widespread
water
stress |
Increased risk of
food and water
shortage;
increased risk of
malnutrition;
increased risk of
water- and foodborne
diseases |
Water shortages for
settlements, industry and societies; reduced
hydropower generation
potentials; potential for
population migration |
Intense
tropical
cyclone activity
increases |
Likely |
Damage to
crops; windthrow
(uprooting) of
trees; damage to
coral
reefs |
Power outages
cause
disruption of
public water
supply |
Increased risk of
deaths, injuries,
water- and foodborne
diseases;
post-traumatic
stress disorders |
Disruption by flood
and
high winds; withdrawal of risk coverage in
vulnerable areas by
private
insurers, potential
for population migrations |
Increased
incidence of
extreme high
sea
level
(excludes
tsunamis) |
Likely |
Salinisation of
irrigation water,
estuaries and
freshwater
systems |
Decreased
freshwater
availability due
to saltwater
intrusion |
Increased risk of
deaths and injuries
by drowning in
floods;
migrationrelated
health
effects |
Costs of coastal protection
versus costs of land-use
relocation; potential for
movement of populations
and infrastructure; also
see tropical cyclones
above |
