Gcm scenarios for regional studies over west africa
This presentation is the property of its rightful owner.
Sponsored Links
1 / 36

GCM Scenarios for Regional Studies over West Africa PowerPoint PPT Presentation


  • 55 Views
  • Uploaded on
  • Presentation posted in: General

GCM Scenarios for Regional Studies over West Africa. Gregory S. Jenkins Department of Meteorology Penn State University. “Africa is Highly Vulnerable to Climate Change.” IPCC 2001.

Download Presentation

GCM Scenarios for Regional Studies over West Africa

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Gcm scenarios for regional studies over west africa

GCM Scenarios for Regional Studies over West Africa

Gregory S. Jenkins

Department of Meteorology

Penn State University


Africa is highly vulnerable to climate change ipcc 2001

“Africa is Highly Vulnerable to Climate Change.”IPCC 2001


Gcm scenarios for regional studies over west africa

“Impact of particular concern that are of particular concern to Africa are related to water resources, food production, human health, desertification and coastal zones especially in relation to extreme events.”IPCC 2001


The overall capacity for africa to adapt to climate change is very low

“The overall capacity for Africa to adapt to climate change is very low”

IPCC 2001


Gcm scenarios for regional studies over west africa

A1B scenario


West african precipitation anomalies

West African Precipitation Anomalies


Objectives of presentation

Objectives of Presentation

  • -Compare NCAR CCM3, CCSM v.1 to NCEP

  • -Identify Biases in models

  • Compare 20-21st century climates of West Africa (5-35N, 20W-40E)

  • CCM3 (Kiehl et al. 1998) - Climatological SSTs

  • CCSM version 1 (Boville and Gent, 1998)


21st century temp prec diff

21st century temp./prec. diff


West african features examined for 20 21st century simulations

200 hPa zonal winds- Tropical Easterly Jet- (TEJ)

700 hPa zonal winds - African Easterly Jet (AEJ)

Precipitation field

African Easterly waves

Meridional temperature gradient

Sea Level pressure fields.

West African Features examined for 20-21st century simulations


Precip observations and ccm

Precip. (Observations and CCM)


Precip observations and ccsm

Precip. (Observations and CCSM)


700 hpa aej simulations

700 hPa AEJ simulations


African easterly waves

African Easterly Waves

  • African easterly waves have

  • 3-5 day periods (Meridional winds) -Burpee, 1972

  • 6-9 day periods - Diedhiou et al. 1999

  • AEJ is modulated on similar time periods.


Ecmwf ccsm u v spectrum

ECMWF/CCSM u,v spectrum


Ecmwf ccsm spectrum of u v

ECMWF/CCSM spectrum of u,v


Ccm3 ccsm u v spectrum

CCM3/CCSM u,v spectrum


Ccm ccsm observational air temps

CCM/CCSM/Observational Air Temps.


Sea level pressure comparison

Sea Level Pressure comparison


Sea level pressure difference

Sea Level Pressure Difference


Sahara warming

Sahara Warming

Why does the Sahara warm more with elevated GHGs?

  • Total warming = increased IR forcing + warm advection (Europe).

  • Feedbacks small

  • Warming shared between Sahara and Europe!


Aej precip shear linkages

AEJ, precip, shear linkages


Shear and precipitation differences 1999 2002

Shear and Precipitation differences (1999-2002)


20 21 century u v spectrum

20-21 century u,v spectrum


Conclusion

Conclusion

  • West Africa simulated better in A1 simulations relative to CCM3 but for wrong reasons.

  • AEJ, AEWs better simulated in CCSM v.1

  • 21st century warming in West Africa uncertain because of competing factors of warm advection from Europe and land use change in West Africa.

  • AEJ frequency shifted to longer timescale in 21st century.

  • CCSM v.1 can be used as boundary conditions for regional climate model simulations.


Initial regional model tests

Initial Regional model tests


  • Login