Climate Change: An Inter-disciplinary Approach to Problem Solving (AOSS 480 // NRE 480)

1. Climate Change: An Inter-disciplinary Approach to Problem Solving(AOSS 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://clasp.engin.umich.edu/people/rbrood Winter 2017 March 7, 2017

2. Class Information and News • Canvas site: CLIMATE_480_001_W17 • Record of course • Rood’s Class MediaWiki Site • http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action • Rood’s Class Tumblr Site: http://openclimate.tumblr.com

3. Resources and Recommended Reading • Rood’s Series on Bumps and Wiggles • Past, Present and Future of Atlantic Meridional Overturning Circulation, Srokosz et al., BAMS, 2012

4. Outline: Class 9, Winter 2017 • Distribution of energy by atmosphere and ocean • “Internal” variability (Redux) • Analysis • How weather and climate is organized • Physical geography • Rotation of Earth • Climate variability and change

5. Energy doesn’t just come and go • The atmosphere and ocean are fluids. The horizontal distribution of energy, causes these fluids to move. That is, weather and ocean currents.

6. From Building the Radiative Balance Redistribution by atmosphere, ocean, etc. RS Top of Atmosphere / Edge of Space 1)The absorbed solar energy is converted to terrestrial thermal energy. 2)Then it is redistributed by the atmosphere, ocean, land, ice, life. CLOUD ATMOSPHERE SURFACE

7. After the redistribution of energy, the emission of infrared radiation from the Earth is ~ equal from all latitudes. Because of tilt of Earth, Solar Radiation is absorbed preferentially at the Equator (low latitudes). Consider the Distribution of Energy Latitudinal dependence of heating and cooling Top of Atmosphere / Edge of Space CLOUD ATMOSPHERE SURFACE South Pole (Cooling) Equator (On average heating) North Pole (Cooling)

8. Transfer of heat north and south is an important element of the climate at the Earth’s surface. Redistribution by atmosphere, ocean, etc. Top of Atmosphere / Edge of Space This predisposition for parts of the globe to be warm and parts of the globe to be cold means that measuring global warming is difficult. Some parts of the world could, in fact, get cooler because this warm and cool pattern could be changed. What is a scenario for record cold temperatures in northern Mexico? CLOUD ATMOSPHERE heat is moved to poles cool is moved towards equator cool is moved towards equator SURFACE This is a transfer. Both ocean and atmosphere are important

9. Transport of heat poleward by atmosphere and oceans • This is an important part of the climate system. • One could stand back far enough in space, average over time, and perhaps average this away. • This is, however, weather ... and weather is how we feel the climate day to day • It will change because we are changing the distribution of heating and increasing the energy in the system.

10. Internal Variability

11. Sources of internal variability • There is “natural” variability. • Solar variability • Volcanic activity • Internal “dynamics” • Atmosphere - Weather • Ocean • Atmosphere-ocean interactions • Atmosphere-ocean-land-ice interactions • “Natural” does not mean that these modes of variability remain constant as the climate changes. Separation of “natural” and “human-caused.”

12. Some Aspects of Climate Variability • One of the ways to think about climate variability is to think about persistent patterns of weather • Rainy periods • Floods • Dry periods • Droughts • During these times the weather for a region does not appear random – it perhaps appears relentless

13. An example of variability: Seasons Warm Cold Cold Temperature Messy Messy Winter Summer Winter Rain comes in thunderstorms Rain comes in fronts Forced variability responding to solar heating

14. Wave Motion and Climate

15. Year-to-Year Changes in Winter Temperatures Differences Relative to 1961-1990 Average Late 1970s 2006-2011 From Jim Hurrell

16. Modes of Climate Variability • Weather – single “events” – waves, vortices • There are modes of internal variability in the climate system which cause global changes. • El Niño – La Niña • What is El Niño • North Atlantic Oscillation • Climate Prediction Center: North Atlantic Oscillation • Annular Mode • Inter-decadal Tropical Atlantic • Pacific Decadal Oscillation

17. LONG SHORT There are short-term issues important to climate change. What is short-term and long-term? Pose that time scales for addressing climate change as a society are best defined by human dimensions. Length of infrastructure investment, accumulation of wealth over a lifetime, ... ENERGY SECURITY Election time scales CLIMATE CHANGE ECONOMY 25 years 0 years 50 years 75 years 100 years

18. LONG SHORT Time Scales of Variability Pacific Decadal Oscillation Arctic Oscillation 25 years 0 years 50 years 75 years 100 years El Niño / La Niña

19. Atmosphere-Ocean Interaction: El-Niño

20. Changes during El Niño

21. Some good El Niño Information • NOAA Climate Prediction: Current El Niño / La Niña • NOAA CPC: Excellent slides on El Niño

22. GISS Temperature 2002 1997-98 El Niño

23. January 2011 Temperature Anomalies El Niño / La Niña Signal

24. Modes of Climate Variability • Weather – single “events” – waves, vortices • There are modes of internal variability in the climate system which cause global changes. • El Niño – La Niña • What is El Niño • North Atlantic Oscillation • Climate Prediction Center: North Atlantic Oscillation • Annular Mode • Inter-decadal Tropical Atlantic • Pacific Decadal Oscillation

25. North Atlantic Oscillation Negative Phase U.S. East, Cold Air Outbreaks, Snow (dry) Europe North, Cold; South, Wet Greenland, Warm Positive Phase U.S. East, Mild and Wet Europe North, Warm and Wet Canada North & Greenland, Cold and Dry

26. January 2011 Temperature Anomalies Arctic Oscillation Signal

27. Modes of Climate Variability • Weather – single “events” – waves, vortices • There are modes of internal variability in the climate system which cause global changes. • El Niño – La Niña • What is El Niño • North Atlantic Oscillation • Climate Prediction Center: North Atlantic Oscillation • Annular Mode • Inter-decadal Tropical Atlantic • Pacific Decadal Oscillation

28. Pacific Decadal Oscillation • Does the Pacific Decadal Oscillation operate regularly lasting 20-30 years, and does southern California experience droughts during that period? • The Pacific Decadal Oscillation is one of several “oscillations” that are important to weather and climate. • Some attributes of the Pacific Decadal Oscillation

29. Pacific Decadal Oscillation: Basics Colors: Sea Surface Temperature difference from long term average. Arrows: Stress on the ocean surface caused by winds Cool here Warm here Better version of figure from JISAO

30. January 2011 Temperature Anomalies Pacific Decadal Oscillation Signal

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

32. How Weather is Organized

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

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

35. Atmosphere

36. Hurricanes and heat: Sea Surface Temperature

37. Weather Moves Heat from Tropics to the Poles HURRICANES

38. Mid-latitude cyclones & Heat

39. 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

40. Ocean

41. Ocean Surface Currents(From Steven Dutch, U Wisconsin, Green Bay) Good Material at National Earth Science Teachers Association

42. The Thermohaline Circulation (THC)(Global, organized circulation in the ocean)(The “conveyer belt”, “rivers” within the ocean) Blue shading, low salt Green shading, high salt Where there is localized exchange of water between the surface and the deep ocean (convection) Warm, surface currents. Cold, bottom currents.

43. In Class / Groups / Discussion • Thermohaline Circulation • Atlantic Meridional Overturning Circulation • In groups discuss Atlantic Meridional Overturning Circulation / Gulf Stream • How does it affect climate? • How does variability affect climate? • Consider: • Temperature, Ice Melting, Wind, Saltiness,

44. Climate variability and change

45. LONG SHORT Time Scales of Variability Pacific Decadal Oscillation Arctic Oscillation 25 years 0 years 50 years 75 years 100 years El Niño / La Niña

46. January 2011 Temperature Anomalies El Niño / La Niña Signal

47. GISS Temperature 2002 1997-98 El Niño

48. Roles of Uncertainty / Variability at Different TimesHawkins and Sutton, 2009

49. Summary: Class 9, Winter 2017 • Distribution of energy by atmosphere and ocean • Greenhouse gases change energy balance • Atmosphere and oceans transport energy • “Internal” variability (Redux) • Modes of internal variability organize weather in spatial and temporal patterns

50. Summary: Class 9, Winter 2017 • How weather and climate is organized • Rotation of Earth • Location of land-water • Tilt of axis • Thermal characteristics • Climate variability and change • Climate change occurs on a background of variability. • We can diagnose the variability, it is more difficult to predict.