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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) [email protected] http://aoss.engin.umich.edu/people/rbrood Winter 2015 February 5, 2015 Class Information and News • Ctools site: AOSS_SNRE_480_001_W15 – Record of course • Rood’s Class MediaWiki Site – http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action • A tumbler site to help me remember – http://openclimate.tumblr.com/ 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 Outline: Class 9, Winter 2015 • 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 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. 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 Consider the Distribution of Energy Latitudinal dependence of heating and cooling Top of Atmosphere / Edge of Space CLOUD ATMOSPHERE 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). SURFACE South Pole (Cooling) Equator (On average heating) North Pole (Cooling) 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 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. Internal Variability 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.” 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 Cold Messy Warm Cold Messy Temperature An example of variability: Seasons Winter Summer Rain comes in fronts Rain comes in thunderstorms Winter Forced variability responding to solar heating Wave Motion and Climate Year-to-Year Changes in Winter Temperatures Differences Relative to 1961-1990 Average Late 1970s 2006-2011 From Jim Hurrell 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 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, ... LONG SHORT Election time scales ENERGY SECURITY CLIMATE CHANGE ECONOMY 0 years 25 years There are short-term issues important to climate change. 50 years 75 years 100 years Time Scales of Variability LONG SHORT Pacific Decadal Oscillation Arctic Oscillation 0 years 25 years El Niño / La Niña 50 years 75 years 100 years Atmosphere-Ocean Interaction: El-Niño Changes during El Niño Some good El Niño Information • NOAA Climate Prediction: Current El Niño / La Niña • NOAA CPC: Excellent slides on El Niño GISS Temperature 2002 1997-98 El Niño January 2011 Temperature Anomalies El Niño / La Niña Signal 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 North Atlantic Oscillation Positive Phase U.S. East, Mild and Wet Europe North, Warm and Wet Canada North & Greenland, Cold and Dry Negative Phase U.S. East, Cold Air Outbreaks, Snow (dry) Europe North, Cold; South, Wet Greenland, Warm January 2011 Temperature Anomalies Arctic Oscillation Signal 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 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 Pacific Decadal Oscillation: Basics Colors: Sea Surface Temperature difference from long term average. Arrows: Stress on the ocean surface caused by winds Warm here Better version of figure from JISAO Cool here January 2011 Temperature Anomalies Pacific Decadal Oscillation Signal 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 How Weather is Organized Projected Global Temperature Trends: 2100 Heat Capacity Heat Transport 2071-2100 temperatures relative to 1961-1990. Special Report on Emissions Scenarios Storyline B2 (middle of the road warming). Land IPCC 2001 Projected Global Temperature Trends: 2100 Heat Capacity Heat Transport 2071-2100 temperatures relative to 1961-1990. Special Report on Emissions Scenarios Storyline B2 (middle of the road warming). Ocean IPCC 2001 Atmosphere Hurricanes and heat: Sea Surface Temperature Weather Moves Heat from Tropics to the Poles HURRICANES Mid-latitude cyclones & Heat 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 Ocean Ocean Surface Currents (From Steven Dutch, U Wisconsin, Green Bay) Good Material at National Earth Science Teachers Association The Thermohaline Circulation (THC) (Global, organized circulation in the ocean) (The “conveyer belt”, “rivers” within the ocean) Blue shading, low salt Where there is localized exchange of water between the surface and the deep ocean (convection) Green shading, high salt Warm, surface currents. Cold, bottom currents. 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, Climate variability and change Time Scales of Variability LONG SHORT Pacific Decadal Oscillation Arctic Oscillation 0 years 25 years El Niño / La Niña 50 years 75 years 100 years January 2011 Temperature Anomalies El Niño / La Niña Signal GISS Temperature 2002 1997-98 El Niño Roles of Uncertainty / Variability at Different Times Hawkins and Sutton, 2009 Summary: Class 9, Winter 2015 • 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 Summary: Class 9, Winter 2015 • 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. Outline: Class 9, Winter 2015 • 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 Projects • Abrupt climate change • Consequences of rapid change in the Arctic • Analysis of the warming “hiatus”