Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
Climate change and disaster risk management
--Is the changing climate affecting disaster risk?
Ian NobleENV Climate Change Team
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
Bulletin of the American Meteorological Society 2010 doi: 10.1175/2010BAMS3092.1
Have disaster losses increased due to anthropogenic climate change?
Laurens M. BouwerInstitute for Environmental Studies, Vrije Universiteit, Amsterdam, The Netherlands
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
BBC Summary -- “…according to scientists, up until now, weather-related natural hazards, with their inherent variability, may have not been increasing – it’s the vulnerability of the population that has seen a sharp rise.”
NHPR -- The paper “… finds no causal link between increases in disaster losses and man-made climate change.”
Study Finds No Link Tying Disaster Losses to Human-Driven WarmingBy ANDREW C. REVKIN NYT
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
Conclusions• The analysis of twenty-two disaster loss studies shows that
economic losses from various weather related natural hazards, such as storms, tropical cyclones, floods, and small-scale weather events such as wildfires and hailstorms, have increased around the globe.
• The studies show no trends in losses, corrected for changes (increases) in population and capital at risk, that could be attributed to anthropogenic climate change.
• Therefore it can be concluded that anthropogenic climate change so far has not had a significant impact on losses from natural disasters.
• Considerable uncertainties remain in some of these studies, as exposure and vulnerability that influence risk can only be roughly accounted for over time.
• In particular the potential effects of past risk reduction efforts on the loss increase are often ignored, because data that can be used to correct for these effects is not available.
“The bottom line? Regardless of what happens due to global warming, on a crowding, urbanizing planet, increased exposure to, and losses from, nature’s hard knocks are a sure thing if people keep settling in harm’s way.” Andrew Revkin
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
What have we observed?
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
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0.08
1972 1977 1982 1987 1992 1997 2002
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LICL-MICU-MICDeveloped
More and more people are being affected by climate related disasters each decade
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
We believe that the increase seen in the graph until about 1995 is explained • partly by better reporting of
disasters in general, • partly due to active data
collection efforts by CRED and • partly due to real increases
in certain types of disasters.
We estimate that the data in the most recent decade present the least bias and reflect a real change in numbers. This is especially true for floods and cyclones. Whether this is due to climate change or not, we are unable to say.
CRED (Centre for Research on the Epidemiology of Disasters)
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
0.00
0.02
0.04
0.06
0.08
1972 1977 1982 1987 1992 1997 2002
Prop
ortio
n of
peo
ple
affe
cted
per
yea
r
LICL-MICU-MICDeveloped
More and more people are being affected by climate related disasters each decade
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
1975 1980 1985 1990 1995 2000 20050
10
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30
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LDCMICUMICHIC
Even
ts p
er y
ear
1975 1980 1985 1990 1995 2000 20050
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60
80
100
120
140
DroughtFloodStormTemp Extr
Even
ts p
er y
ear
1975 1980 1985 1990 1995 2000 2005 20100.0
500,000.0
1,000,000.0
1,500,000.0
2,000,000.0
f(x) = 38622.1538621585 x − 75638363.4609224R² = 0.440109284679355
People affected per flood event
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
0
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1880 1900 1920 1940 1960 1980 2000 2020
Clim
ate
: phy
sical
disa
ster
ratio
Unusually low number of physical disasters in early 1960s & 1970s
Unusually high number of climate disasters in early
2000s
Climate related disasters are increasing faster than non-climate disasters
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
-14 -12 -10 -8 -6 -4 -2 0-20%
-10%
0%
10%
20%
CPIA 2005 Improving --->
<---
Bett
er R
ate
of ch
ange
Wor
se --
->
LDCs – governance seems to matterPercent change in people affected per 5 years
Area of dot represents number of people affected
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
What can we learn from climate modelling?
Increase annual max number consecutive dry days (<1 mm) Kamaguchi SOLA 2006
Blue – Cooler conditions (-3 to 19 °C)Pink – Mild conditions (19 to 29 °C)Red – Hot conditions (29 to 35 °C)
Warmer conditions more moisture in air heavier ppt events
Fraction of annual rainfall falling in extreme events (>95% of current)
Changes in flood frequency
1 In 100 year flood returns every 20 years1 in 20 year flood returns every 6 years
100-drought frequency 2020Lenher et al 2006 Climatic Change
Cyclone intensityWebster et al 2005 Science 309, 1844
• Noda et al Earth Simulator from Oouchi et al 2005
• Cyclone frequency at end of 21st C
• Overall frequency will fall but number of intense events will increase
But don’t expect much detail on cyclone paths
In a 4 °C scenario, most land surface temperature increases will be well above 4 °C
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
It is not all about extremes and disasters.
Imagine living through summer after summer in an ‘Oslo’ designed house relocated to central Spain
Workshop on Disaster Risk Management and Climate Change Adaptation Washington DC, September 2010
Takeshi Enomoto, Earth Simulator Center/JAMTEC Cloud representation at 320 km grid (Left) versus 20 km (Right) for the same point in a model run
Seasonal forecasting - NOAA
• 1, 3 & 5.5 month precipitation forecast
• But essentially little useable information beyond 1 month
Which “Early Warning Systems”
are feasible?