1. Climate Change: The Move to Action (AOSS 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://aoss.engin.umich.edu/people/rbrood Winter 2010 February 11, 2010

2. Class News Ctools site: AOSS 480 001 W10AOSS 480 001 W10 On Line: 2008 Class2008 Class –Reference list from courseReference list from course Rood Blog Data Base Reading

3. Make Up Class / Opportunity Make up Class on March 8, Dana 1040, 5:00 – 7:30 PM, Joint with SNRE 580 –V. Ramanathan, Scripps, UC San DiegoV. Ramanathan, Scripps, UC San Diego –Please consider this a regular class and make it a priority to attend. Pencil onto calendar on April 6, Jim Hansen, time TBD.

4. Class Projects Think about Projects for a while –The role of the consumer –Energy efficiency / Financing Policy –Science influence on policy, Measurements of carbon, influence –Role of automobile, transportation, life style –Water, fresh water, impact on carbon, –Geo-engineering, public education, emergency management, warning, –Water, insurance, Midwest development, Michigan, regional –Dawkins, socio-biology –What leads to a decision –What does it really mean in the village –Geo-engineering, urban sustainability –US Policy, society interest, K-12, education

5. Project Teams Michigan Coal / Energy: Maggiet Allan, Meghan Reynard, Evan Oswald, Yoichi Shiga Efficiency as effective mitigation: Rebecca Taylor, Erin Kashawlic, Rajesh Nerlikar, Amanda Herrick

6. Projects; Short Conversation “Geo-engineering” --- managing heating in the near-term / Role of Attribution / Managing the climate, what climate information is needed / Air quality Transportation / Automobiles / Energy / Market / Weather / Extreme Events / Agriculture / Carbon Sinks / Local Adaptation

7. Next week Groups that have organized a short presentation, discussion –Title –Your vision –What disciplines are present in your group

8. Today: complete the basic picture we need Aerosols Internal Variability Feedbacks: Response to a change in forcing Important details that we have to remember –Land surface / land use changes –Other green house gases –Air quality –Abrupt climate change

9. Summary Points Theory / Empirical Evidence CO 2 and Water Vapor Hold Heat Near Surface Correlated Observations CO 2 and Temperature Observed to be strongly related on long time scales (> 100 years) CO 2 and Temperature not Observed to be strongly related on short time scales (< 10 years) Observations CO 2 is Increasing due to Burning Fossil Fuels Theory / Conservation Principle Mass and Energy Budgets  Concept of “Forcing”

10. Let’s look at just the last 1000 years Surface temperature and CO 2 data from the past 1000 years. Temperature is a northern hemisphere average. Temperature from several types of measurements are consistent in temporal behavior. Note that on this scale, with more time resolution, that the fluctuations in temperature and the fluctuations in CO 2 do not match as obviously as in the long, 350,000 year, record. What is the cause of the temperature variability? Can we identify mechanisms, cause and effect? How? {

11. Aerosols Aerosols are particulate matter in the atmosphere. –They impact the radiative budget. –They impact cloud formation and growth.

12. Some important things to know about aerosols They can directly impact radiative budget through both reflection and absorption. They can indirectly impact radiative budget through their effects on clouds  both reflection and absorption. They have many different compositions, and the composition matters to what they do. They have many different, often episodic sources. They generally fall out or rainout of the atmosphere; they don’t stay there very long compared with greenhouse gases. They often have large regional effects. They are an indicator of dirty air, which brings its own set of problems. They are often at the core of discussions of geo-engineering

13. Radiative Forcing IPCC 2007

14. Sources of internal variability This is natural variability. –Solar variability –Volcanic activity –Internal “dynamics” Atmosphere - Weather Ocean Atmosphere-ocean interactions That does not mean that these modes of variability remain constant as the climate changes.

15. Internal Variability? There are modes of internal variability in the climate system which cause global changes. –El Nino – La NinaEl Nino – La Nina What is El Nino –North Atlantic OscillationNorth Atlantic Oscillation Climate Prediction Center: North Atlantic Oscillation –Annular ModeAnnular Mode –Inter-decadal Tropical Atlantic –Pacific Decadal OscillationPacific Decadal Oscillation

16. Some good El Nino Information NOAA Climate Prediction: Current El Nino / La NinaNOAA Climate Prediction: Current El Nino / La Nina NOAA CPC: Excellent slides on El Nino –This is a hard to get to educational tour. This gets you in the middle and note navigation buttons on the bottom.

17. GISS Temperature 2002 1997-98 El Nino An interesting time to study?

18. Some information on Pacific Decadal Oscillation Joint Institute for Study of Atmosphere and Ocean (JISAO):JISAO –Pacific Decadal OscillationPacific Decadal Oscillation Climate Prediction Center (CPC):CPC –90 Day Outlook Summary90 Day Outlook Summary –Weather and Climate LinkageWeather and Climate Linkage National Climatic Data Center (NCDC):NCDC –Decadal OscillationsDecadal Oscillations Review Paper from Rood Class References –Mantua and Hare (2002) J of OceanographyMantua and Hare (2002) J of Oceanography

19. Today: complete the basic picture we need Aerosols Internal Variability Feedbacks: Response to a change in forcing Important details that we have to remember –Land surface / land use changes –Other green house gases –Air quality –Abrupt climate change

20. So what matters? Things that change reflection Things that change absorption Changes in the sun If something can transport energy DOWN from the surface. THIS IS WHAT WE ARE DOING

21. More consideration of radiative energy in the atmosphere FEEDBACKS.... –The idea that one thing causes a second thing to happen. That second thing then does something to the first thing –It damps it, negative feedback –It amplifies it, positive feedback –Technical Reference: Soden and HeldSoden and Held

22. The Earth System: Feedbacks 1 Infrared Proportional to Temperature SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared) Assume that greenhouse gases remain the same Infrared emission is proportional to temperature Temperature increases  emission increases

23. The Earth System: Feedbacks 2 Water Vapor When it gets warmer more water, a greenhouse gas, will be in the atmosphere Higher temperature increases evaporation from land and ocean Higher temperature allows air to hold more water Increase of water increases thickness of blanket – increases temperature more This could runaway! Natural limit because of condensation  clouds, rain? Compensating circulation changes? Think deserts … SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared)

24. The Earth System: Feedbacks 3 Ice - Albedo ICE Top of Atmosphere / Edge of Space When it gets warmer less ice Less ice means less reflection  warmer Warmer means less ice This could runaway! Cooler works the other way  ice-covered

25. The Earth System: Feedbacks 4 Clouds? SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared) Clouds are difficult to predict or to figure out the sign of their impact Warmer  more water  more clouds More clouds mean more reflection of solar  cooler More clouds mean more infrared to surface  warmer More or less clouds? Does this stabilize? Water in all three phases essential to stable climate CLOUD

26. The Earth System: Feedbacks 5 Something with the Ocean? Is there something with the ocean and ice? Land ice melting decreases ocean salinity (density) Sea-ice impacts heat exchange between ocean and atmosphere Sea-ice impacts solar absorption of ocean North Atlantic sea-ice and ocean interaction very important to the climate Think Gulf Stream Think climate and people and economy Is there a natural feedback that stabilizes climate? Even if there is, it would be very disruptive, perhaps not stable from a societal point of view.

27. Cloud-Ice-Atmosphere Feedback Some carry away messages –This is where much of the discussion about scientific uncertainty resides. –The Earth is at a complex balance point That balance relies on water to exist in all three phases. –Too warm could run away to “greenhouse” vapor –Too cold run away to “snowball” ice –How clouds change is not well understood and much argued. The Iris Effect?The Iris Effect –Is there something in all of this that changes the sign; namely, that CO 2 warming will be compensated by more cooling?

28. CLOUD-WORLD Earth System: Ice ATMOSPHERE LANDOCEAN ICE (cryosphere) SUN ICE: Very important to reflection of solar radiation Holds a lot of water (sea-level rise) Insulates ocean from atmosphere (sea-ice) Ice impacts both radiative balance and water – oceans and water resources on land.. Large “local” effects at pole. Large global effects through ocean circulation and permafrost melting. Might change very quickly.

29. The Earth System: ICE (Think a little more about ice) non-polar glaciers and snow polar glaciers (Greenland) (Antarctica) sea-ice Impacts regional water supply, agriculture, etc. Solar reflection, Ocean density, Sea-level rise Solar reflection, Ocean-atmosphere heat exchange (Tour of the cryosphere, Goddard Scientific Visualization Studio)

30. The Cryosphere TOUR OF CRYOSPHERE: MAIN NASA SITETOUR OF CRYOSPHERE: MAIN NASA SITE

31. Let’s think about the Arctic for a while WWF: Arctic Feedbacks Assessment

32. Projected Global Temperature Trends: 2100 2071-2100 temperatures relative to 1961-1990. Special Report on Emissions Scenarios Storyline B2 (middle of the road warming). IPCC 2001

33. The Thermohaline Circulation (THC) (Global, organized circulation in the ocean) (The “conveyer belt”, “rivers” within the ocean) Where there is localized exchange of water between the surface and the deep ocean (convection) From Jianjun Yin, GFDL, see J. Geophysical Research, 2006 Warm, surface currents. Cold, bottom currents. Green shading, high salt Blue shading, low salt

34. The Earth System ATMOSPHERE LAND OCEANICE SUN Solar variability Water vapor feedback accelerates warming Ice-albedo feedback accelerates warming Increase greenhouse gases reduces cooling rate  Warming Changes in land use impact absorption and reflection Cloud feedback? Aerosols cool? Cloud feedback?

35. The predictions and observations so far are either in the sense of: –Relatively small changes in the dynamic balance of the climate system –Incremental changes to the stable climate. What about “abrupt” climate change? Abrupt climate change

36. Note to professor: Force students to think and speak What might cause something to change abruptly in the climate system? Lamont-Doherty: Abrupt Climate Change NAS: Abrupt Climate Change Wunderground.com: Abrupt Climate ChangeWunderground.com: Abrupt Climate Change

37. What is a stable climate? NOAA Paleoclimate Schlumberger LIQUID - ICE

38. Younger Dryas POSSIBLE EVIDENCE OF CHANGE IN OCEAN CIRCULATION WHAT DOES THIS MEAN?

39. Next time: Fundamental Science of Climate