The Arctic Climate Paquita Zuidema, RSMAS/MPO, MSC 118, March 2 2007.
-
Upload
kelley-reynolds -
Category
Documents
-
view
215 -
download
0
Transcript of The Arctic Climate Paquita Zuidema, RSMAS/MPO, MSC 118, March 2 2007.
annual
IncreasedSpringAndSummerCloudiness
1982-1999AVHRR data(Wang&Key, 2003)
Persistent springtime cloud cover may advance snowmelt onset date (e.g., modeling study of Zhang 1996)
spring
summer
annual
IncreasedSpringAndSummerCloudiness
1982-1999AVHRR data(Wang&Key, 2003)
Persistent springtime cloud cover may advance snowmelt onset date (e.g., modeling study of Zhang 1996)
spring
summer
Surface-based Instrumentation: May 1-8 time series
35 GHz cloud radarice cloud properties
depolarization lidar-determined liquid cloud base
Microwave radiometer-derived liquid water paths
4X daily soundings. Near-surface T ~ -20 C, inversion T ~-10 C
-5-45 -20
1 2 3 4 5 6 7 8day
z
-30C
41 8
2
4
6
8
km
100g/m^2
day
-10C
lidar cloud base
How do clouds impact the surface ?
noon = 60o
Clouds decrease surface SW by 55 W m-2 ,increase LW by 49 W m-2
Surface albedo=0.86; most SW reflected backClouds warm the surface, relative to clear skies with same T& T & RH, by time-mean 41 W m-2* (little impact at TOA)
• Can warm 1m of ice by 1.8 K/day, or melt 1 cm of 0C ice per day, barring any other mechanisms !
Great websites with real-time data, historical fotos:
http://www.arctic.noaa.gov/
http://nsidc.orghttp://nsidc.org/cryosphere/glancehttp://nsidc.org/data/seaice-index/