What do I need to know?What do I need to know?What do I need to do?
Is the earth’s atmosphere warming?Is the earth’s atmosphere warming?Is this warming causing climate change?Are humans impacting on this warming?If so, what can I do about it?
Review global temps for last 150 yearsReview global temps for last 150 yearsVariations in last 150 19th century – constant; Rise in early 20th; Level off in mid 20th; Rapid rise 1990-2009 - Why?What causes this pattern?Early – volcanoes, sun; Later – Burning fossil fuelsVariations on global average tempsLand warmer than ocean; More increase towards polesAverage temps have risen about 1.5 degrees since start of 20th century. Is this significant?
Surface temps are not only indicators of warmingSurface temps are not only indicators of warmingEarths’ inner temps; Upper levels of oceans; Lower levels of atmosphere warming - upper levels coolingEarth’s cryosphere (snow & ice cover) is decreasingGlaciers, Arctic ice, Ice caps, Ice sheets - ReflectionsWeather patterns over decades show changesMore extreme hot and cold; Precipitation changes, Night temps; Increase in hurricanesPlants and animal species are movingNH moving northward and upward – 6 miles – 6 feet; Springtime events earlier : 2-3 days (per decade)
Energy balance – between incoming sunlight and radiated heat lossEnergy balance – between incoming sunlight and radiated heat lossSun sends in ultraviolet rays; Planet sends out infrared rays – Earth balances out at zero (0) degreesEarth’s atmosphere causes “greenhouse effect”Atmosphere is 80% nitrogen, 20% oxygen – transparent to sun’s incoming rays and Earth’s outgoing raysWater vapor and CO2 is transparent to sun’s incoming ultraviolet rays BUT opaque to Earth’s outgoing infrared rays – Result – increase in Earth’s temp to 60 degrees
Neighboring planets (Mars, Venus) can provide us with a “greenhouse experiment”Neighboring planets (Mars, Venus) can provide us with a “greenhouse experiment”Comparison of Temps – No AtmosphereMars: -90 F; Earth: o F; Venus: 110 FComparison of Temps – With AtmosphereMars: -120 F; Earth: 60 F; Venus: 500 F (melt lead)Comparison of AtmospheresMars: 1% (.01) of Earth’s density; Cooler – reflects heatEarth: 1.0 density – provides normal greenhouse effectVenus: 100 times Earth’s density – 96% is CO2; All water is evaporated – powers greenhouse effect; CO2 - permanent
Three factors affect temps – two are natural, one is usThree factors affect temps – two are natural, one is us1. VolcanoesThrows dust into air; forms clouds; decreases temps2. SunBurn rate varies; distance from Earth; tilt of Earth axis3. Anthropogenic – caused by humansBurn fossil fuels – increases CO2 in atmosphereOther factorsMethane (minor); Aerosals – particles in airWhy blame us?Strong correlation – CO2 , higher temps; Natural causes - varying effects; Dominant correlation in recent decades has been anthropogenic
There will be a steady rise in global tempsThere will be a steady rise in global tempsMost likely 3-8 degrees; Drop of 11 degrees would bring new Ice Age; Increase of 9 degrees – tropics in NHExtreme weather events will increase – greater fluctuation in weatherHeat waves; Intense precipitation; Droughts; Intense tropical stormsSea levels will riseAverage will be 6”- 18” (maybe 20); Caused by warmer water, not melting ice; Salt water will encroach on freshPolar advances of species will accelerate
Two questions: 1. Do we have it? 2. Can we get it?Two questions: 1. Do we have it? 2. Can we get it?Three main sources of energy: 1. SunSolar, Wind – Expensive; Limited; Variable availability – cloud cover, no air moving2. Fossil FuelsNatural gas – burns cleaner; Oil – running out (decades left); Coal – dirtiest, but most abundant (300 years left); Nuclear – cleanest, but most dangerous3. Tidal wavesRivers, dams, ocean waves – limited, most being used already
Some people insist this is just an unproven theorySome people insist this is just an unproven theoryScientists have trouble communicating this to the general publicClimate change can be confusing and upsetting to peopleSolutions will have serious economic and lifestyle impactsPolitical differences among government leaders impacts progress towards solutions
1. There is a difference between weather and climate1. There is a difference between weather and climate2. Global warming is accelerating and is caused mainly by humans burning fossil fuels3. Global warming is causing climate change and will have a significant impact on people and nature4. Earth’s temperatures will most likely rise 3-8 degrees by the year 2100.5. Sea levels have already risen and are projected to rise much more6. There is scientific consensus that global warming is causing climate change and presents us with some serious challenges
7. Governmental leaders from many countries are working on international agreements to deal with climate change7. Governmental leaders from many countries are working on international agreements to deal with climate change8. New technologies must be developed to stabilize and reduce greenhouse gases9. Saving energy and developing alternative energy sources will help10. Every individual person can take actions daily to help with this situation
Turn off electrical devices when not in useTurn off electrical devices when not in useTake shorter showersClose blinds/drapes on hot, sunny daysTurn off lights when you leave a roomSwitch to fluorescent light bulbsPlant treesCombine and reduce trips in carsRecycle whenever possiblePurchase recycled productsSpread the word – encourage wise energy consumption
List of Websites List of Websiteswww.Knowledge.Allianz.comEn.wikipedia.org/wiki/Global_warmingwww.epa.gov/climatechangewww.gobalwarming.orgwww.climatehotmap.org/NationalGeographic.comwww.nwf.org/[email protected] (North Carolina information)