CLIMATE RESEARCH IN THE DEPARTMENT OF PHYSICS
W. Healey, MALTA CLIMATE TEAM
14-19th March 2011
Evaluating the Land Surface Model of the Regional
Climate Model PRECIS
•Why the climate?
-The weather patterns over a period of years.
-The Impact of the climate.
•How do we do it?!
-Computer models running
simulations of parameters
-Different scales:
Global, Regional and Local
300 km
50km
•How do we do it?!
250 m
-Computer models running
simulations of parameters
-Different scales:
Global, Regional and Local
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The effect of the surface on climate…
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The effect of the surface on climate…
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… in the climate model
Dynamic Core
Radiation
LSM
Clouds
Aerosols
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Providing REgional Climates for Impact Studies (PRECIS)
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Providing REgional Climates for Impact Studies (PRECIS)
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The details
• A 60 year study from 1960 till 2020
• Taking parameters most affected by the land
surface – temperatures and moisture levels
• Comparing the LSMs with Measured Data
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Met Office Surface Exchange Scheme – the LSM
9 different surface types:
Broadleaf trees, needleleaf trees, temperate
grass, tropical grass, shrubs, bare soil, Ice, Urban
and lake/inland water
Upgrades over the older version include:
•Height of vegetation in calculations
•Shortwave / longwave radiation
• Soil flooding
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Results part I
MOSES 1
MOSES 2.2
Average surface temperature
from 1960 to 1990
Measured
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Results part II
Temperature (˚C)
Surface temperature
Time (Years)
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Results part III
Relative Humidity (%)
Relative Humidity
Time (Years)
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Conclusions
•PRECIS is still relatively weak in predicting the measured results.
• Spatial plots reveal an over prediction in tropical regions and an
under prediction in temperate regions.
• Time series for surface temperature shows on average an over
prediction of about 0.3 ˚C in models.
• Whilst an under prediction of around 3% for relative humidity.
• MOSES2.2 results do not show improvement in PRECIS’
performance compared to measured data.
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Thank you!
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