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Theme 4: Scales and Sustainability Ecological Effects of Climate Driven Processes Through Time Kelly T. Redmond Western Regional Climate Center Desert Research Institute Reno Nevada Mojave Desert Science Symposium University of Redlands Redlands California November 16-18, 2004.
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Theme 4: Scales and Sustainability Ecological Effects of Climate Driven Processes Through Time Kelly T. Redmond Western Regional Climate Center Desert Research Institute Reno Nevada Mojave Desert Science Symposium University of Redlands Redlands California November 16-18, 2004
Some general points about climate Climate and fluctuation Fluctuation and variability: an inherent property of climate Energy and mass Reservoirs Flows Typically driven by spatial gradients Thresholds (including phase changes of key constituents) Temporal scales Microseconds to eons - approx 16 orders of magnitude Boundary conditions on one scale are initial conditions at others High and low pressure areas for the next five minutes Sea surface temperature for tomorrow’s forecast Continental positions for the next millennium Spatial scales Microns to planetary - approx 10 orders of magnitude Climate entails constant fluctuation, at all scales Fluctuation at one scale is stasis at another scale Snail vs turtle perspective
Change and fluctuation in desert environments Deserts are defined by aridity, but water is the major driver of change Highly skewed precipitation statistics Yuma: 17 days per year with precipitation (every 21 days) 51 hours of precipitation annually (0.6 % of the time) 12 percent of the annual average falls during the wettest hour Annual average falls in one day about once per hundred years Very unlikely that these are stationary statistics What is a sufficient averaging interval for calculating event rates? Deserts spend most of their time in “waiting” mode – military analogy Wind somewhat less troublesome, statistically, but still not easy Temperature more tractable. Temp, Wind, Rel Hum always present. Recharge highly nonlinear, mountains and heavy thunderstorms Climate behavior in driest environments is tied to wettest areas
CA Stovepipe Wells 1 SW, Death Valley National Park (Climate Reference Network) 36.6 N 117.1 W 80’ May 6, 2004
Reanalysis Resolution: Global Regional (slightly smaller; pixel resolution)
Oct-Mar Apr-May-June Fraction of Annual Total Precipitation, by Season July-Aug
Jan Percent of Annual Precipitation Feb Mar Apr
May Percent of Annual Precipitation Jun Aug Jul
Sep Percent of Annual Precipitation Oct Nov Dec
Chaos and nonlinear dynamics: Does this subject have a role? On the face of it, immediate practical applications seem elusive. However, there seems much to offer in terms of appreciating limitations of knowledge of behavior of system components. Fundamental and theoretical limitations, what is simply not possible. Practical limitations, so we don’t waste our time on the wrong things. The subject seems to have a great deal of value in informing us how strongly to hold on to certain beliefs about our ability to direct events in preferred directions. It also brings up the subject of predictability: Under what circumstances is prediction even possible? What situations might be more predictable than others? (“more predictable” = greater likelihood of correct outcome) When should we refrain from prediction, when should we try? This is a major area of inquiry in climate and atmospheric science. Combined physical and biological systems are incredibly complicated. How predictable is the evolution of ecological systems?
“Life must be lived forward, but it can only be understood backward.” - Soren Kierkegaard
Sat 2004 Nov 14 00 GMT - 000 hr Sat 2004 Nov 14 0000 GMT - 000 hr Ensemble Forecasting - 23 members NOAA Climate Diagnostics Center
000 Hr Forecast NOAA Climate Diagnostics Center
Sat 2004 Nov 14 0000 GMT - 024 hr Sat 2004 Nov 14 0000 GMT - 048 hr NOAA Climate Diagnostics Center
Sat 2004 Nov 14 0000 GMT - 072 hr Sat 2004 Nov 14 0000 GMT - 120 hr NOAA Climate Diagnostics Center
120 Hr Forecast Wed Eve Nov 24 2004 00 GMT 5 PM PST NOAA Climate Diagnostics Center
Sat 2004 Nov 14 0000 GMT - 168 hr Sat 2004 Nov 14 0000 GMT - 240 hr NOAA Climate Diagnostics Center
Sat 2004 Nov 14 0000 GMT - 360 hr Sat 2004 Nov 14 0000 GMT - 360 hr NOAA Climate Diagnostics Center
360 Hr Forecast NOAA Climate Diagnostics Center
Sea Surface Temperature Departure from Average Week of 2004 Oct 31 – Nov 06 NOAA Climate Diagnostics Center
Seasonal precipitation outlook Nov-Dec-Jan 2004-05 EC means Equal Chances (no forecast !)
Six models, 12 opinions, for Northern California. 1900-2100 Precipitation Temperature Thanks to Mike Dettinger, Scripps / USGS
Trends 1966+ Annual, Full Year. Trends 1966+ Feb-Mar-Apr Source: Climate Prediction Center
Southern Nevada Climate Division Nov-April Precipitation 1895-2004
Southern Nevada Climate Division Nov-April Temperature 1895-2004
For sustainability: The climate backdrop may be changing.
Desert Drought: How do you recognize it ???
Standardized Precipitation Index Percentile 01 – Month thru Oct 2004
Standardized Precipitation Index Percentile 12 – Month thru Oct 2004
Standardized Precipitation Index Percentile 72 – Month thru Oct 2004
Standardized Precipitation Index Percentiles Southern Nevada All Time Scales 01 – 72 months