Transcript Geography 120 Earth Systems II: The Atmospheric Environment

Geog 1900: ExtremeWeather and Climate
Review of last lecture
• The modern climatology (meteorology) was born in the
1940s (a very young science!), but has been growing
very fast! Now we have a global observational network
with many satellites, ships, radars and surface
stations, as well as very comprehensive prediction
models running on the world’s fastest supercomputers.
• The current status of weather and climate predictions:
(1) weather prediction good to 10 days, (2) tropical
cyclone prediction good in track but not in intensity,
(3) climate prediction good to two seasons, (4) climate
change projections have a 3-fold difference in
magnitude.
Overview III: Why is it so difficult
to predict weather and climate?
Problem I: Different parts of the world are
strongly connected to each other
(The “Teleconnection Problem”)
Global atmospheric flow
Satellite image: Flow of water vapor in
the atmosphere
Example 1: Global impacts of El Nino
The “Pineapple Express”
connecting Hawaii and California
Example 2: Global impacts of the mini
El Nino (Madden-Julian Oscillation)
Factors affecting US weather and
climate
Arctic
N. Atlantic
Atlantic/
Sahel
Madden-Julian
Oscillation
El Nino
Amazon
Any location is affected by all the other
locations, and in turn is affecting all the
other locations
Problem II: Different components of the earth
system (atmosphere, land, ocean, ice, clouds, etc)
are strongly interacting with each other
(The “Feedback Problem”)
Example: Melting of Arctic sea ice
Video: Ice Albedo feedback
• http://www.youtube.com/watch?v=5rqREjFaRho
Problem III: The global climate models divide the earth
into many small pixels (called grids), but the earth system
composes of both very big objects (such as the whole Pacific
Ocean) and very small objects (such as the cloud droplets),
making it very difficult to draw them on the same page
(The “Subgrid-Scale Problem”)
The limitation of concept/theory/model:
Only approximation of real world
Concepts cut reality into smaller pieces
Some Great
Weather/Climate Scientists
Prof. Lonnie Thompson –
OSU
• Father of Tropical Glaciology
• Spent an enormous amount
of time above 5500 m
• Discovered solid record for
Earth’s climate history
• Grown up in West Virginia
• Did three part-time jobs in
high school to make a living
• Worked for many years with
low salary
• Went back to the Himalayas
after heart transplant
Prof. Robert Cess
SUNY at Stony Brook
• World’s leading expert on climate
change and Earth’s energy budget
• Organized the first international
team for supercomputer
prediction of global climate
change, and many NASA and
DOE projects
• Was not even an AMS Fellow
when received the Charney Award
• Finished his Ph.D. in 3 years
while doing a full-time job and
taking care of his first child
• Hobby: Collectible cars
The young generation
Video: Prof Dargan Frierson and Elizabeth
Maroon sing The World of Daisies (lyrics
by Prof Mike Wallace) in ATM S 111:
Global Warming
• https://www.youtube.com/watch?v=kYyS
TtFcQlU
Summary
• The main reasons of the difficulties in weather
and climate predictions: (1) Teleconnection
problem, (2) Feedback problem, and (3)
Subgrid-scale problem
• Some great weather/climate scientists