Presentation on theme: "Introduction to Climate Science"— Presentation transcript:
1Introduction to Climate Science Virginia Office of Environmental Education
2Approach for the DaySummarize some of the key scientific findings, with discussion of time & space scales.Provide some reference materials for further inquiry.Give Virginia examples of climate concerns.
3Terms to KnowScienceClimateGreenhouse EffectMilankovitch Cycles
4What is Science?The systematic observation of natural events and conditions in order to discover facts about them and to formulate laws and principles based on these facts.- Academic Press Dictionary of Science & TechnologyScience is a way of learning about the natural world and the knowledge gained through that process.- Prentice Hall, Science Explorer Grade 6To do science is to search for repeated patterns, not simply to accumulate facts.- Robert H. MacArthur, Geographical Ecology
5Terms to KnowScienceClimateGreenhouse EffectMilankovitch Cycles
6What is Climate?Climate is the average, year-after-year conditions of temperature, precipitation, winds, and clouds in an area.- Prentice Hall, Science Explorer, Grade 6Climate is determined by the long-term pattern of temperature and precipitation averages and extremes at a location.- Climate Literacy, U.S. Global Change Research Program
7Is the planet’s climate changing in significant ways? Scientists agree that warming of the climate system is occurring due observations of:Increases in global average air and ocean temperaturesWidespread melting of snow and iceRising global average sea levelSource: Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Solomon, S., et al., (eds). [hereafter IPCC 2007 WG1-AR4 ]
8Terms to KnowScienceClimateGreenhouse EffectMilankovitch Cycles
9Why is the Greenhouse Effect important? The greenhouse effect helps maintain a consistent temperature on the planet Earth which makes our planet livable.
10Greenhouse Effect 1824 – Discovery is attributed to Joseph Fourier Reliably experimented on by John TyndallWater Vapor (H2O), Carbon Dioxide (CO2), Ozone (O3), and Methane (CH4)Reported quantitatively by Svante Arrhenius
11What is the Greenhouse Effect? The greenhouse effect is a process by which radiative energy leaving a planetary surface is absorbed by some atmospheric gases, called greenhouse gases. They transfer this energy to other components of the atmosphere, and it is re-radiated in all directions, including back down towards the surface. This transfers energy to the surface and lower atmosphere, so the temperature there is higher than it would be if direct heating by solar radiation were the only warming mechanism.
13Terms to KnowScienceClimateGreenhouse EffectMilankovitch Cycles
14What are the Milankovitch Cycles? Named after the Serbian astronomer Milutin MilankovitchTheorized effects of changes in the Earth’s movements upon its climateEccentricityObliquityPrecession (Wobble)
15Eccentricity – Orbital shape ~ 100,000 year cycle
18What is the relationship between Milankovitch Cycles and Greenhouse Gases? Historic data shows that CO2 levels have never been above ppm in the historic record420,000 years of ice core data from Vostok, Antarctica research stationCO2Temp.CH4
19Climate Change Responses Are Not Geographically Uniform Source:Are these changes in temperature affecting all of the world at the same time?
20Life on Earth depends on and is shaped by the affects of Climate. Organisms exposed to climate conditions outside their normal range must adapt or migrate, or they will perish.Individual organisms survive within specific ranges of temperature, precipitation, humidity, and sunlight.
21Over the past 30 years in Oxfordshire, U. K Over the past 30 years in Oxfordshire, U.K., the average arrival and departure dates of 20 migrant bird species have both advanced by 8 days.There is mounting evidence that global climate change has extended growing seasons, changed distribution patterns, and altered the phenology of flowering, breeding, and migration.Proceedings of the National Academy of the Sciences
22What about Virginia?Historic month-to-month temperature averages from NOAAFrost date and growing season length changesSewell’s Point tide gauge
23time [years] time [years] time [years] What we see in observations is a trend superimposed onto the natural variability.Tides rise and fall, daytime temperatures are higher than nighttime temperatures, summer temperatures are warmer than winter temperatures … there are many things in nature that go up and down over time in a fairly regular manner.There are also things that can monotonically increase or decrease (e.g., atmospheric greenhouse gas levels since the 19th century).Simply add together the linear trend and the sine wave shown in this schematic and you get the yellow curve… a curve with a clear upward trend over the long term, but one that contains shorter term downward periods.To my eye, the yellow curve qualitatively resembles area-averaged measures of temperatures and other climate variables we see both in observations and in our climate models when forced by monotonically increasing greenhouse gas levels.Bottom line: Both human-induced trends and natural variability can and do occur at the same time. The existence of one does not preclude the other.23
42What does this mean for Virginia? Rising TemperatureRising Sea LevelLonger growing season from the shifting frosts
43How will the Earth’s climate change? Scientists agree globally that:Wet areas will get wetter and dry areas will get drierFrequency of extreme weather events may increaseSea level will rise
44How is science addressing these changes? Scientists are:Taking better and morecomprehensive observationsDeveloping improved climate modelsDeveloping regional assessmentsbased on local observation data
45Next Steps Learn more Review the Virginia Plan www.climate.gov
46Do Something Assess your two footprints: Be active in your community Carbon FootprintEcological FootprintBe active in your community
47Recap Science Climate Greenhouse Effect Milankovitch Cycles Virginia examplesNext Steps to Do Something
48Introduction to Climate Science Virginia Office of Environmental Education