Global Climate Predictions Greg says…(read above) We have looked at what is climate, natural influences of climate, evidence of GCC, how climate models have improved. Now we are going to look at prediction of the models or interpretation of the model outcomes Next we are going to look at consequences if these projections are correct We will end class with way to mitigate GCC

Objectives Describe the projections of climate models in relations to global average temperatures, sea level, surface temperatures by region, precipitation, frost days, heat days, and growing days. Describe the projections of Greenland and melting of the ice sheets.

Outline Global Average Surface Temperature Sea level Surface Temperature by Region Precipitation Frost, Heat, Growing days Melting Greenland Hurricanes Comparing predictions with actual outcomes is a fundamental tool of science. Comparing the scenario generated by a climate model with real world conditions is a test for the model—and for the understanding of natural processes that the model represents.

Assumptions on Scenarios http://en.wikipedia.org/wiki/Special_Report_on_Emissions_Scenarios W2012 SRM adds this page to clarify what we are modeling. Some “notes” in this Pp are wrong. Following the link and briefly describe A and B scenarios. The graph shows the CO2 projections for next 100 years for each scenario. 2006 2026 2046 2066 2086

Projected Temperature and Sea Level Changes This makes no sense (SRM 2012) These models used CO2 @ 2000 ppm to run projections. Is this a good model? Not really, fossil fuel usage has gone up over time as has the CO2 in the atmosphere

Surface Temperatures a more divided world. a world more integrated, and more ecologically friendly balanced emphasis on all energy sources. These are three different model projections a more divided world.

2020-2029 2090-2099 A1B See http://www.ipcc.ch/publications_and_data/ar4/wg1/en/figure-10-6.html A2

Changes in precipitation Winter Summer Latitudes = Tropical 0-20,deserts centered at 23, temperate 30-60ish, polar. White represents areas of uncertainty, where less than two-thirds of models agreed on whether precipitation would increase or decrease. Stippled areas indicate where 90% of the models agreed on the sign of the change. Connect to first day of class: climate map, biome map. Increased ppt at tropics and poles. Decreased at subtropics. Drier Mediterranean.

SUMMER WINTER

Standard Deviation The standard deviation is a measure of the spread of a set of values from the mean value. Deviation from a long-term average. Standard deviation is a widely used measure of variability or diversity used in statistics and probability theory. It shows how much variation or "dispersion" exists from the average (mean, or expected value). A low standard deviation indicates that the data points tend to be very close to the mean, whereas high standard deviation indicates that the data points are spread out over a large range of values

Frost days defined as the total number of days in a year with absolute minimum temperature below 0°C Globally averaged changes in the frost day index (defined as the total number of days in a year with absolute minimum temperature below 0°C) for a low (SRES B1), middle (SRES A1B) and high (SRES A2) scenario. http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-6-2.html GR climate data http://www.climate-charts.com/USA-Stations/MI/MI203333.php

Heat Waves European heat waves 2003 heat waves in Europe, we didn’t hear much about them because the American news is very US-centric, however listening to new like the BBC you would have heard more about these heat waves because they give a more global perspective

Growing Season http://www.arborday.org/media/mapchanges.cfm

Melting Greenland 4X pre-industrial levels would be 80/100 = 800ppm in 1000yrs. 1120ppm-370ppm (current level)=750ppm 280 ppm x 2 = 1120 ppm

Melting Greenland FIG. 4. The rates of change of ice sheet volume (dark line) and area (light line) during the GHG2 simulation. Different phases of the ice sheet evolution are described in the main text. http://epic.awi.de/Publications/Rid2005a.pdf

Hurricanes? Some believe that with increased GCC hurricanes will increase in number & intensity However…(see next slide) This slide is showing the number of hurricanes has increased since 1900 from an average of 10 to an average of 15 storms per year. (This is only showing frequency of Atlantic storms)

Increased temp should increase hurricane activity; some models predict (but limited by grid spacing); may be patterns (see above)….ongoing research http://www.gcrio.org/ipcc/qa/08.html