A Growing Interest 2: Climate and Plants Asheville, NC March 22, Thomas C. Peterson NOAA’s National Climatic Data Center Asheville, North Carolina What Lies Ahead

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Outline of the talk: The basic physics of climate change science Implications of this physics –On temperature and precipitation Projected changes relevant to the plant sector A bit on impacts

A Growing Interest 2: Climate and Plants Asheville, NC March 22,

A Growing Interest 2: Climate and Plants Asheville, NC March 22, We need the greenhouse effect The Earth’s surface temperature is ~60ºF Without the greenhouse effect it would be ~5ºF But humans are changing the radiative properties of the atmosphere and thereby the greenhouse effect

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Ravishankara (2006) Warming versus cooling effects are like the tortoise versus the hare. Climate Forcing Summary

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Do you believe in global warming? I believe in quantum physics.

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Quantum physics tells us that Infrared (IR) energy can only be absorbed and radiated in very small particle-like packets of energy called quanta

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Quantum physics tells us that Infrared (IR) energy can only be absorbed and radiated in very small particle-like packets of energy called quanta Each molecule can absorb and radiate quanta at different wavelengths

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Quantum physics tells us that Infrared (IR) energy can only be absorbed and radiated in very small particle-like packets of energy called quanta Each molecule can absorb and radiate quanta at different wavelengths Two atom molecules can absorb very little IR energy –E.g., Nitrogen (N 2 ) and Oxygen (O 2 ) 98% of the atmosphere

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Quantum physics tells us that Infrared (IR) energy can only be absorbed and radiated in very small particle-like packets of energy called quanta Each molecule can absorb and radiate quanta at different wavelengths Two atom molecules can absorb very little IR energy –E.g., Nitrogen (N 2 ) and Oxygen (O 2 ) 98% of the atmosphere Three or more atom molecules do absorb and radiate in the IR –E.g., Carbon Dioxide (CO 2 ), water vapor (H 2 O), methane (CH 4 ) 2% of the atmosphere CO 2 only 0.04% of the atmosphere

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Are CO 2 and other greenhouse gasses really responsible for changing the global temperature? Ice cores can give us the long view

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Are CO 2 and other greenhouse gasses really responsible for changing the global temperature? The long view says they are definitely related Vostock ice core data from Petit et al., 1999; current CO 2 data from NOAA (Tans 2007)

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI, 2009 Atmospheric carbon dioxide is predicted to rise to concentrations not seen in perhaps 25 million years –Pekar 2008

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Scenarios Future warming depends on how much greenhouse gases are emitted Several different scenarios were developed based on possible changes in –Population –Rate of adoption of new technologies –Economic growth –But not policies

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI 2009 Data through 2007 Kaya identity: CO 2 emissions from human sources = (population)x(GDP/capita)x(Energy/GDP)x(CO 2 /energy) Hence 2008 emission likely to be lower than 2007’s. Data for 2008 available in June 2009.

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Not from climate A to climate B Projections to end of century gives appearance of climate change ending then Plan for continual change –Where the rate of change is most relevant

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Clausius–Clapeyron relationship

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI, 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Humidity increases are greatest where temperatures are highest Peterson et al., 2011

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Temperature increases are highest where humidity is lowest Peterson et al., 2011

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI, 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22, As climate warms, hardwood trees out-compete evergreen trees that are adapted to colder conditions GCCI, 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22,

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Projected Shifts in Forest Types Mid-range warming scenario GCCI, 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22, GCCI, 2009

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Ecosystems processes, such as those that control growth and decomposition, have been affected by climate change. Climate change has strong influence on the processes that control growth and development in ecosystemsClimate change has strong influence on the processes that control growth and development in ecosystems Temperature increases can:Temperature increases can: –Speed up plant growth, especially weeds –Rates of decomposition –How rapidly the cycling of nutrients occurs Kudzu vines

A Growing Interest 2: Climate and Plants Asheville, NC March 22, Climate change is here and now and in our own backyards In the U.S., spring now arrives an average of 10 days to two weeks earlier than 20 years ago In the U.S., spring now arrives an average of 10 days to two weeks earlier than 20 years ago –The growing season is lengthening over much of the continental U.S. –Many migratory bird species arrive earlier Photograph by Robert Lubeck: Animals Animals—Earth Scenes

A Growing Interest 2: Climate and Plants Asheville, NC March 22,

A Growing Interest 2: Climate and Plants Asheville, NC March 22, The End