Changing Climate . . . Linkages to LA Agriculture. Jay Grymes WAFB Chief Meteorologist LSU AgCenter Climatologist. LSU AgOutlook 2010 21 January 2010. “Global Warming” generally refers to the apparent warming of - PowerPoint PPT Presentation
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Changing Climate . . . Changing Climate . . . Linkages to LA AgricultureLinkages to LA Agriculture
““Global Warming”Global Warming” generally refers to the apparent warming ofgenerally refers to the apparent warming of the Earth over the past 100+ years . . . andthe Earth over the past 100+ years . . . and impliesimplies a human impact or influence a human impact or influence
““Climate Change”Climate Change” refers to periodic shifts -- and temporal andrefers to periodic shifts -- and temporal and spatial variability -- of Earth’s local, regional,spatial variability -- of Earth’s local, regional, and global climateand global climate maymay include a human factor, but acknowledges include a human factor, but acknowledges that these variations have always occurredthat these variations have always occurred “ “climate change” is more than the changes inclimate change” is more than the changes in temperaturetemperature
Think of these as Think of these as ‘Confidence Maps’ ‘Confidence Maps’
and not indicators of and not indicators of the amount of the amount of
departuredeparture
What about Louisiana’s Climate?What about Louisiana’s Climate?
-- has demonstrated change over the last-- has demonstrated change over the last100+ years 100+ years
-- changes and variability are not identical-- changes and variability are not identicalacross the stateacross the state
-- changes are not necessarily 1-directional-- changes are not necessarily 1-directional
““To understand the impacts and importance of To understand the impacts and importance of variability and change, we recognize the state’s long-variability and change, we recognize the state’s long-
term climatic patterns”term climatic patterns”
Comparison of Monthly Average Rainfall:Comparison of Monthly Average Rainfall:NW LA vs. SE LANW LA vs. SE LA
‘‘Wet’ October --Wet’ October -- generally ‘wet’ statewidegenerally ‘wet’ statewide
CurrentCurrent El Niño . . . El Niño . . .expected to persist atexpected to persist at
‘‘moderate to strong’ intensitymoderate to strong’ intensityinto Spring 2010into Spring 2010
La Niña
La Nada
El Niño
ENSO – El Niño / Southern OscillationENSO – El Niño / Southern Oscillation
Three Phases:Three Phases:El Niño El Niño (“warm” ocean phase)(“warm” ocean phase)La Niña La Niña (“cool” ocean phase)(“cool” ocean phase)La Nada La Nada (“neutral” ocean temps)(“neutral” ocean temps)
El Niño
La Niña
La Nada
U.S. Rainfall Trends since mid-1960sU.S. Rainfall Trends since mid-1960s(Dark Green = 2”+ per decade)(Dark Green = 2”+ per decade)
SourceSource: NOAA National Climatic Data Center: NOAA National Climatic Data Center www.ncdc.noaa.eduwww.ncdc.noaa.edu
Regional / local scale Regional / local scale variability in moisture variability in moisture
characteristicscharacteristics
SourceSource::Nat’l Climate Data CenterNat’l Climate Data Center www.ncdc.noaa.govwww.ncdc.noaa.gov
The ‘Acknowledged’ Global Temperature RecordThe ‘Acknowledged’ Global Temperature Record
The ‘Acknowledged’ Global Temperature RecordThe ‘Acknowledged’ Global Temperature Record
Source:Source:Surface Temperature Reconstructions for the Last 2,000 YearsSurface Temperature Reconstructions for the Last 2,000 Years (2006). (2006).
National Research Council, National Academy of Sciences.National Research Council, National Academy of Sciences.National Academies Press, Washington, DC.National Academies Press, Washington, DC.
““Little IceLittle Ice Age”Age”
““Medieval WarmMedieval WarmPeriod”Period”
Fischer et al, 2002
A Warmer, COA Warmer, CO22 ‘Enriched’ Atmosphere . . . ‘Enriched’ Atmosphere . . .
Possible:Possible:- significant warming- significant warming- substantial drop in rainfall in LA- substantial drop in rainfall in LA
American Assoc. of State Climatologists (2001)American Assoc. of State Climatologists (2001)
““. . . climate predictions have not demonstrated skill . . . climate predictions have not demonstrated skill in projecting future variability and changes in . . . in projecting future variability and changes in . . .
“ “ [However][However] . . . effective mitigation/adaptation . . . effective mitigation/adaptation policies and strategies need not depend on the policies and strategies need not depend on the
precision and confidence in future predictions …”precision and confidence in future predictions …”
. . . and . . .. . . and . . .
“… “… a lack of predictive skill in GCMs should not be a lack of predictive skill in GCMs should not be used as a justification to avoid policy development used as a justification to avoid policy development
and implementation that fosters ‘environmental and implementation that fosters ‘environmental stewardship’ and ecological responsibility.”stewardship’ and ecological responsibility.”
AASC (2001)AASC (2001)
Source: Dr. Virginia Burkett, USGSSource: Dr. Virginia Burkett, USGS
At a 2006 EPA workshop, I proposed:At a 2006 EPA workshop, I proposed:““Even if the threat of global warming/climate change Even if the threat of global warming/climate change
is being overstated, the most ‘modest’ of impacts is being overstated, the most ‘modest’ of impacts could have dire effects on Louisiana . . .could have dire effects on Louisiana . . .
Louisiana may be the most adversely impactedLouisiana may be the most adversely impacted of any state in the nation.” of any state in the nation.”
One guy’s perspective?!?One guy’s perspective?!?
Jay GrymesJay GrymesWAFB Chief MeteorologistWAFB Chief Meteorologist