A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 1

Thomas C. Peterson

NOAA’s National Climatic Data CenterAsheville, North Carolina

What Lies AheadWhat Lies Ahead

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 2

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, 2012 3

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 4

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, 2012 5

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, 2012 6

Do you believe in global warming?

• I believe in quantum physics.

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 7

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, 2012 8

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, 2012 9

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 (N2) and Oxygen (O2)

• 98% of the atmosphere

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 10

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 (N2) and Oxygen (O2)

• 98% of the atmosphere

• Three or more atom molecules do absorb and radiate in the IR– E.g., Carbon Dioxide (CO2), water vapor

(H2O), methane (CH4)• 2% of the atmosphere• CO2 only 0.04% of the atmosphere

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 11

Are CO2 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, 2012 12

Are CO2 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 CO2 data from NOAA (Tans 2007)

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 13GCCI, 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, 2012 14

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, 2012 15GCCI 2009

Data through 2007

Kaya identity:  CO2 emissions from human sources = (population)x(GDP/capita)x(Energy/GDP)x(CO2/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, 2012 16

GCCI 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 17

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, 2012 18

Clausius–Clapeyron relationship

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 19

GCCI, 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 20

Humidity increases are greatest where temperatures are highest

Peterson et al., 2011

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 21

Temperature increases are highest where humidity is lowest

Peterson et al., 2011

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 22

GCCI, 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 23

As climate As climate warms, warms, hardwood hardwood trees out-trees out-compete compete evergreen evergreen trees that are trees that are adapted to adapted to colder colder conditionsconditions

GCCI, 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 24

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 25

Projected Shifts in Forest Types

Mid-range warming scenario

GCCI, 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 26

GCCI, 2009

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 27

Ecosystems processes, such as those that control growth and decomposition, have been affected by climate change.• Climate change has strong Climate change has strong

influence on the processes that influence on the processes that control growth and development control growth and development in ecosystemsin ecosystems

• Temperature increases can:Temperature increases can:– Speed up plant growth, especially Speed up plant growth, especially

weedsweeds– Rates of decompositionRates of decomposition– How rapidly the cycling of nutrients How rapidly the cycling of nutrients

occursoccurs

Kudzu Kudzu vinesvines

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 28

Climate change is here and now and in our own backyards

• In the U.S., spring now arrives an average of 10 In the U.S., spring now arrives an average of 10 days to two weeks earlier than 20 years agodays to two weeks earlier than 20 years ago– The growing season is lengthening over much of the continental The growing season is lengthening over much of the continental

U.S.U.S.– Many migratory bird species arrive earlierMany migratory bird species arrive earlier

Photograph by Robert Lubeck: Animals Animals—Earth Scenes

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 29

A Growing Interest 2: Climate and Plants

Asheville, NC March 22, 2012 30

The End