Climate science in a world with global change

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Climate science in a world with global change

• David Noone
• Program in Atmospheric and Oceanic
  SciencesCooperative Institute for Research in
  Environmental SciencesUniversity of Colorado,
  Boulder, CO

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Global change

• Changes to atmospheric composition (greenhouse
  gases, aerosols, )
• Changes to surface conditions (deforestation,
  agriculture, urbanization, water use)
• How does climate system (atmosphere, ocean,
  cryosphere, biosphere) respond?What processes
  (physical, chemical, biological) govern change?
• Cloud processes, global hydrologic cycle,
  atmosphere-biosphere interaction

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Research to quantify global change

• Models of climate (and global environment)
• Observed trends
• Use of (mostly physical) models to understand
  impacts on chemical and biological systems
• What are the feedbacks/couplings between
  physical-chemical-biological systems?
• Are these different during Earths history
  (e.g., Ice ages? Warm periods?)

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Radiative forcing of climate
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Terrestrial ecosystem/biosphere change

• Terrestrial biosphere/atmosphere interaction
• Not just response
• Identification and quantification of feedbacks
  between atmosphere and terrestrial biosphere
• Specifically water and carbon cycling in the
  presence of total energy balance
• Role of ecosystem change and resource use (e.g,
  logging, water use/availability) on surface
  energy balance
• temperature, humidity, wetness
• Role of global circulation in modifying surface
  processes
• Succession of plant species, further modification
  of land surface)
• Possible sustainable states in the climate system
• What is, and what limits, the global climate and
  ecosystem change?

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Models of atmosphere/biosphere connections
water cycle linked to carbon cycle and vegetation
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Global dimming?
Reconstructed annual reflectance anomalies from
earthshine
CO2
CO18O
Sunlight reflected by earth tends to make dark
side of the moon brighter. Brighter moon means
dimmer earth.
Palle et al., Science, 2004
Coincidence? Or could this be a biospheric signal?
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Motivation for global change science

• Perceived need for research in global
  environmental change drives funding for research
• Without global change, climate science would be
  far more poorly funded!
• There is a real conflict of interest in the
  scientific community catastrophic conclusions
  lead to more funding!
• Is global change science objective?