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Pacific Northwest Weather and Climate, Past, Present and Future George H. Taylor October, 2007

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NCDC US HCN (1221 STATIONS)

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Another problem: compromised station locations

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A study of springtime mountain snowpack in the Pacific Northwest showed widespread declines in snowpack since 1950 at most locations with largest declines at lower elevations indicating temperature effects. Substantial declines (some in excess of 50%) were common in the Cascades, especially in Oregon. Mote, Philip W., Martyn Clark, and Alan F. Hamlet, 2004. Variability and Trends in Mountain Snowpack in Western North America. 15th Symposium on Global Change and Climate Variations, Seattle, Washington.

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Sea Level

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The Arctic

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In the Arctic, temperatures in recent decades have gone up

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But an examination of the entire record shows a different story:

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Changes in Solar Radiation

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The Solar Connection DIRECT EFFECTS Solar brightness or irradiance variations relatively small (IPCC correct) INDIRECT EFFECTS UV warming through ozone chemistry Changes in low clouds through changes in cosmic rays

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R 2 = 0.59 R 2 = 0.64 for 3 year lag temp vs TSI NCDC Annual Mean US Temperature vs Hoyt Schatten TSI Gleissberg Cycle

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NASA is predicting that the next solar cycle will be moderate but that the one after will be very weak.

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Some conclusions: 1.The primary mode of variability in climate over multi- decadal periods in the Northwest appears to be the PDO. 2.Surface temperature is not a good metric for assessing global climate change (uneven measurement patterns, local interferences). Other parameters should be used. 3.Adapting to weather extremes is prudent, and allows us to adapt to climate extremes as well. 4.There are many aspects of climate which are not well understood. 5.This is a great place to live!

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The End

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What Fraction of Global Warming is Due to the Radiative Forcing of Increased Atmospheric Concentrations of CO2? IPCC View: 58% of the radiative forcing of well-mixed greenhouse gases result from CO2 48% of the human-caused warming (climate forcing) result from the radiative effect of CO2. IPCC View: 58% of the radiative forcing of well-mixed greenhouse gases result from CO2 48% of the human-caused warming (climate forcing) result from the radiative effect of CO2.

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New Relative Contribution Percent of the Radiative Effect of CO2 (watts / meter squared) Methane +0.8 Short-wave albedo change +0.5 Tropospheric ozone +0.3 Aerosol black carbon +0.2 Black carbon on snow and ice +0.3 Semi-direct aerosol effect +0.1 Glaciation effect +0.1 Solar influences +0.25 The CO2 contribution to the radiative warming decreases to 26.5% using the IPCC framework Methane +0.8 Short-wave albedo change +0.5 Tropospheric ozone +0.3 Aerosol black carbon +0.2 Black carbon on snow and ice +0.3 Semi-direct aerosol effect +0.1 Glaciation effect +0.1 Solar influences +0.25 The CO2 contribution to the radiative warming decreases to 26.5% using the IPCC framework

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Glaciers are melting, and the rate of melt is increasing. Glacier Park may have no glaciers before long.

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Pederson, G.T., Fagre, D.B., Gray, S.T. and Graumlich, L.J. 2004. Decadal-scale climate drivers for glacial dynamics in Glacier National Park, Montana, USA. Geophysical Research Letters 31: 10.1029/2004GL019770.

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