Post on 09-Mar-2016
description
Chapter 1: Defining the Mid-Summer Drought Chapter 2: Mid-Summer Drought Forcings Chapter 3: Predictability for mid-summer rainfall Chapter 4: The Sequel
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Mr. Joseph Occupation: cabbage farmer Location: Flagaman, Jamaica
Martin Hilton Occupation: tomato farmer Location: Potsdam, Jamaica
Leroy Dixon Occupation: tomato / cassava farmer Location: Potsdam, Jamaica
Earl Bent Occupation: melon farmer Location: Top Hill, Jamaica
Donovan Campbell Occupation: PhD student Location: UWI Mona
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Intra-Americas Sea “Mid-Summer Drought”
The early and late summer is wet, but the middle of my
summer is usually hot and dry. What do you call this?
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This is what we think, but can you tell us what causes our mid-summer
drought?
* Courtesy of Donovan Campbell from The University of The West Indies at Mona
El Nino composite precipitation time series
Some people tell me that the Pacific can influence our rainfall. Is this true?
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Sea level pressure (dry MSD composite)
Sea level pressure (wet MSD composite)
spring NAO pattern
Well, then does the Atlantic play a role
too?
North Atlantic Subtropical High
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Allen et al. 2010
Observed
A) Observed simultaneous and lagged covariance statistics are used to predict the future state of a dynamical system.
B) The state system described by the LIM is constructed based on physical mechanisms that govern the system.
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*Alexander et al., 2008, Journal of Climate
( represents the best “forecast” for 𝑥(𝑡 + 𝜏 given 𝑥(𝑡 )
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2.
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STATE SYSTEM
Simultaneous and lagged covariance matrix
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5 x 5
matrix
SST SST
SLP SLPd
NAO NAOdt
precip precip
zonal wind zonal wind
( the observed simultaneous and lagged covariance statistics matrix )
( these are the state variables that describe the physical system )
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• Investigate MSD “regionality”
within the IAS with farmer
interviews in the eastern
Caribbean (hopefully this
summer)
• Improve our MSD conceptual
model
• Exploit the LIM method to
forecast mid summer rainfall
anomalies within the IAS
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