Download Slide 1

yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

IPCC Fourth Assessment Report wikipedia, lookup

Climate change, industry and society wikipedia, lookup

Surveys of scientists' views on climate change wikipedia, lookup

Effects of global warming on humans wikipedia, lookup

Public opinion on global warming wikipedia, lookup

Scientific opinion on climate change wikipedia, lookup

Climate change feedback wikipedia, lookup

Climatic Research Unit documents wikipedia, lookup

Solar radiation management wikipedia, lookup

Climate change and poverty wikipedia, lookup

Attribution of recent climate change wikipedia, lookup

Climate change in the United States wikipedia, lookup

Climate sensitivity wikipedia, lookup

Media coverage of global warming wikipedia, lookup

Global Energy and Water Cycle Experiment wikipedia, lookup

Climate change and agriculture wikipedia, lookup

Effects of global warming wikipedia, lookup

Global warming wikipedia, lookup

General circulation model wikipedia, lookup

Citizens' Climate Lobby wikipedia, lookup

Global warming hiatus wikipedia, lookup

Climate change in Tuvalu wikipedia, lookup

Carbon Pollution Reduction Scheme wikipedia, lookup

Instrumental temperature record wikipedia, lookup

Politics of global warming wikipedia, lookup

Climate engineering wikipedia, lookup

Climate governance wikipedia, lookup

Climate change adaptation wikipedia, lookup

Global warming controversy wikipedia, lookup

Economics of global warming wikipedia, lookup

Fred Singer wikipedia, lookup

Climate change denial wikipedia, lookup

Effects of global warming on human health wikipedia, lookup

Michael E. Mann wikipedia, lookup

Climatic Research Unit email controversy wikipedia, lookup

Intergovernmental Panel on Climate Change wikipedia, lookup

Soon and Baliunas controversy wikipedia, lookup

Climate resilience wikipedia, lookup

Heaven and Earth (book) wikipedia, lookup

ExxonMobil climate change controversy wikipedia, lookup

2009 United Nations Climate Change Conference wikipedia, lookup

German Climate Action Plan 2050 wikipedia, lookup

Myron Ebell wikipedia, lookup

Conference on Reduction of vulnerability of West Africa to climate change
Ouagadougou, January 24-27 2007
A climate scientist's perspective on recent environmental trends
in the Sahel: a model for future change?
Alessandra Giannini
IRI for Climate and Society (IRI)
The Earth Institute at Columbia University
Outline – past, present and future of climate in the Sahel
1. oceanic forcing dominant in late 20th century droughts
- what role for land-atmosphere interaction?
2. late 20th century response to anthropogenic forcings
- roles of GreenHouse Gases and (sulfate) aerosols
3. why the uncertainty in projections of future change?
- mechanisms of monsoon change under climate change
r = 0.60
A. Giannini, R. Saravanan and P. Chang, 2003. Science, 302, 1027-1030
Also see e.g. Bader and Latif, 2003 (GRL); Lu and Delworth, 2005 (GRL);Tippett, 2006 (GRL)
land-atmosphere interaction: is it a positive feedback?
(soil moisture, vegetation, dust..., evaporation, cloud cover...)
late 20th century surface temperature changes
regression of NASA/NSIPP1 Sahel PC and sfc temp
Giannini et al. 2003, 2005
NASA/GISS analysis of surface temp – linear trend 1950-2000
Hansen et al. 1999 (J. Geophys. Res.)
IPCC 4AR: end 20th century – PreIndustrial sfc temp difference
Biasutti and Giannini 2006 (GRL)
IPCC 4AR simulations – late 20th century climate change
19 Coupled GCMs
XX-PI Changes
Biasutti and Giannini, GRL 2006
20th century
Biasutti and Giannini, 2006 (GRL)
Sahel climate change
21st century
19 Coupled GCM (IPCC 4AR):
recent and future temperature
(end 21st)
- end 20th
end 20th
- PreInd
CONCLUSIONS (climate science)
African climate variability and change are inextricably tied
to variations and trends in the global climate system:
-->> recent trends in the global oceans and in continental precipitation can
in part be ascribed to anthropogenic forcings
-->> drought in the Sahel was forced by a warming of the oceans, in no
negligible part due to GHG and aerosol forcing
“Farmers freed of blame for Sahel drought” in
CONCLUSIONS (climate science informing policy)
Climate change is already here the recent climate shift in the Sahel is a prime example of
potential changes to come, as the global climate system
responds to anthropogenic forcings
-->> regional institutions/CILSS have an opportunity to take advantage of the
lessons learned from managing the climate shift of the last ~30 years
-->> harmonization of desertification and climate change issues is overdue!
CONCLUSIONS (climate science informing practice - climate risk management)
collaborate on climate science
● improve (two-way) communication
-->> between climate scientists and policymakers
-->> between climate scientists and stakeholders in sectors vulnerable to climate
West Africa:
0-20N, 20W-20E
Eastern eq Africa:
10S-10N, 20-50E
Southern Africa:
25-10S, 20-40E
West Africa:
0-20N, 20W-20E
Eastern eq Africa:
10S-10N, 20-50E
Southern Africa:
25-10S, 20-40E
Courtesy of Todd Mitchell, UW/JISAO
Giannini et al., 2005 (Clim. Dyn.)
The relative roles of Atlantic, Indian and Pacific SSTs
Lu and Delworth, 2005 (Geophys. Res. Lett.)
Held et al., PNAS 2005
air temperature
(minus global mean)
Haarsma et al., GRL 2005
2050-2080 minus 1950-1980