Man Made Climate Change vs' Natural Variability - PowerPoint PPT Presentation

1 / 5
About This Presentation
Title:

Man Made Climate Change vs' Natural Variability

Description:

Man Made Forcings. Physically understood mechanisms. Greenhouse Gas Levels ... Man Made Climate Change is different from Natural Variability in the Climate System ... – PowerPoint PPT presentation

Number of Views:139
Avg rating:3.0/5.0
Slides: 6
Provided by: rcum6
Learn more at: https://iri.columbia.edu
Category:

less

Transcript and Presenter's Notes

Title: Man Made Climate Change vs' Natural Variability


1
Man Made Climate Changevs.Natural Variability
Presented By Mark Seaman Sam Atwood
EESC W4400
2
Natural Variability in the Climate System
  • Long-Term
  • Glacial / Interglacial Periods
  • Variability over 10s to 100s of thousands of
    years
  • Max 4C to 6C change over a Glacial /
    Interglacial cycle
  • Variations in Orbit, and Ice Sheet Cover and
    other Feedbacks
  • Short-Term
  • Last several Millennia
  • Max /- 0.2C change over a century
  • Solar Irradiance and Volcanism
  • Not constant on all time or spatial scales
  • Little Ice Age and Medieval Warm Period

Benin
Source Jones, P.D., and M.E. Mann (2004)
3
Anthropogenic Impact on Climate System
  • Typical natural range of variability exceeded in
    20th Century
  • 0.6 to 0.9C change
  • Man Made Forcings
  • Physically understood mechanisms
  • Greenhouse Gas Levels
  • Climate Sensitivity 1.5C to 4.5C with doubling
    of CO2
  • Sulfate Aerosols
  • Land Use Changes
  • Last half of 20th Century
  • Anthropogenic impacts dominate over Natural
    Variability

Source Jones, P.D., and M.E. Mann (2004)
4
Temperature Variations in Last Millennium
Source IPCC Climate change 2001 - Synthesis
report
5
Primary Take Home Points
  • Man Made Climate Change is different from Natural
    Variability in the Climate System
  • This difference
  • Timescale The time of the change is quicker
  • Spatial scale Mean trends for the entire planet
  • Magnitude The direction and amount of change

Questions?
Write a Comment
User Comments (0)
About PowerShow.com