Presentation Transcript
Real Science or Reel Science?: Real Science or Reel Science? Presented by:
Lis Cohen
Meteorology Graduate Student
National Science Foundation WEST Fellow
University of Utah
Outline: Outline Can New York City go from hot to freezing in a few hours? Does climate change happen that fast?
Is it true that the North Atlantic current could shut down?
Is it realistic that a giant wave could hit New York City because of a hurricane?
If air from the upper atmosphere is brought down to the surface in a hurricane, will it freeze us?
Can big storms create giant tornados in LA?
Can New York City go from hot to freezing in a few hours? Does climate change happen that fast? : Can New York City go from hot to freezing in a few hours? Does climate change happen that fast?
Climate change does not happen that fast or dramatically!
Ocean temperature changes take a long time
Large heat capacity
Large ocean volume
Ocean currents could change over many years
Is it true that the North Atlantic current could shut down? : Is it true that the North Atlantic current could shut down?
The ocean surface transfers heat to the atmosphere!
Animation by Jack Cook (Woods Hole Oceanographic Institute)
What process could change the ocean circulation?: What process could change the ocean circulation?
Can giant hurricanes exist all around the world?: Can giant hurricanes exist all around the world? Clusters of thunderstorms cannot merge together to form a continent-scale blizzard with a calm eye over land.
Huge storms with calm eyes happen over the oceans not over land.
Hurricanes or Tropical Storms
Require that the core of the storm be over warm ocean water Photo: earthobservatory.nasa.gov/NaturalHazards/Arch...
If air from the upper atmosphere is brought down to the surface in a hurricane, will it freeze us?: If air from the upper atmosphere is brought down to the surface in a hurricane, will it freeze us? Closer to the Earth’s surface, the air pressure is higher than higher up in the atmosphere. As we bring the air down to the Earth the air pressure increases. As we apply pressure to air, air warms instantaneously!
Bring air which is -80º C from 15km (tropopause) down to the surface
Temperature change because of pressure changes
15km*6º/km(for dry air)= +90ºC
Original temp + temp change = temp at surface
-80ºC+90ºC=10ºC
Change to Fahrenheit
10ºC*(9/5)+32=50ºF
Can ice sheets melt and build overnight?: Can ice sheets melt and build overnight? Ice Sheets and Glaciers
Immense mass prevents rapid melting of ice sheets.
Ex. Climate quickly changed at the end of last ice age
Decades and centuries later the ice sheets and deep ocean adjusted. (NSIDC)
The major ice sheets over North America at the peak of the last ice age took tens of thousands of years to build up. (NASA)
http://daily.greencine.com/archives/day-after-tomorrow.jpg
Is it realistic that a giant wave could hit New York City because of a hurricane?: Is it realistic that a giant wave could hit New York City because of a hurricane? http://www.movie-vault.com/images/news/rainyorkbig.jpg http://i.a.cnn.net/cnn/2004/SHOWBIZ/Movies/05/27/
day.tomorrow/story.day.tomorrow.jpg
Tsunami vs. Storm Surge: Tsunami vs. Storm Surge TSUNAMI
Arrives quickly as a large wave or movement of water onto the shore
Causes
Earthquakes
Submarine Landslide
Calving of glaciers
Tend to be localized events
Antarctic ice collapse would not likely reach the US. STORM SURGE
Arrives as a rise in water in a period of a few hours.
Causes
Low pressure of a storm lifts up the surface of the ocean (only a few feet)
Winds pushing water onto the land
Wind speeds would need to be at least twice the speed of sound (1200 mph) to create a 300ft storm surge. Data from: Dr. Jeffrey M. Masters
Can big storms create giant tornados in LA? : Can big storms create giant tornados in LA? Ingredients for a tornado:
Unstable Atmosphere
Moisture
Little wind sheer
Los Angeles
Stable atmosphere
Little moisture
Conclusion: Conclusion Climate change can not happen as quickly as the movie portrays.
Scientists’ prediction models show a possible slow down and/or adjustment to the North Atlantic current, but not a shut down.
Tsunamis not hurricanes, create waves like in the movie.
If air from the upper atmosphere is brought down to the surface, we will have warm temperatures.
Giant tornados in Los Angeles are very unlikely.
Slide13: Questions?
What process could most likely change the climate?: What process could most likely change the climate? Warmer climate More evaporation at the equator More moisture in the air More moisture can be held in the air More rain at higher latitudes More freshwater in the ocean Ocean is not as salty and dense Water does not sink in the northern latitudes Circulation slows down
and changes Melting Glaciers
How does ocean circulation affect local climates?: How does ocean circulation affect local climates? Intergovernmental Panel on Climate Change (IPCC), "Climate Change 2001: The Scientific Basis" Warm surface current- Less Dense
Cold deep water current–More Dense
Salty water anywhere- More Dense Answer: Heat release locations are warmer!
What is happening with ice shelves today?: What is happening with ice shelves today? Today shifting climate
Antarctic Peninsula the ice shelves are no longer stable. The northern most limit for ice shelves has moved south over the past two decades by about 100 miles. (NSIDC) http://images.amazon.com/images/P/B0007PALRU.01.LZZZZZZZ.jpg
Three Glaciers Retreating: Three Glaciers Retreating Source: C.L. Andrews. 1912, 1938. Denver Glacier: From the Glacier Photograph Collection . Boulder, CO: National Snow and Ice Data Center. Digital Media; Marion T. Millett. 1958. Denver Glacier: From the Glacier Photograph Collection . Boulder, CO: National Snow and Ice Data Center. Digital Media.
How fast can the atmosphere and ocean respond to each other?: How fast can the atmosphere and ocean respond to each other? El Nino-
Winds weaken and ocean responds
This change can happen on the time scale of weeks.
Atmosphere
Readjusts within days ex. Moving jet streams
What directions do warm and cold water currents travel?: What directions do warm and cold water currents travel?
Animation by Jack Cook (Woods Hole Oceanographic Institute)
How do we know about past climates?: How do we know about past climates? Ice sheets reveal annual layers
history of precipitation and air temperatures 100,000 years in the past.
Flash Freezing: Flash Freezing The superstorm sucks vast quantities of frigid upper atmospheric air down to the surface, flash freezing any living thing caught outside. However, any graduate of a high school physics course could tell you that the air would warm on its descent in response to the requirements of the Ideal Gas Law, and would never be able to flash freeze anything. One scientist in the movie does remember his high school physics and asks, "But wouldn't the air warm as it descends?" But the senior scientist replies, "No, it's moving too fast!" Sorry, guy, but the Ideal Gas Law applies no matter how fast the air is moving. If you were on my thesis committee, I'd kick you off.
by Dr. Jeffrey M. Masters Chief Meteorologist, The Weather Underground, Inc.
Storms flowing opposite directions: Storms flowing opposite directions The superstorm is shown in many scenes rotating clockwise, and in other scenes counter-clockwise. Oops, all large-scale storm systems in the Northern Hemisphere must rotate counter-clockwise, thanks to one of the laws of physics on a rotating planet called the Coriolis force.
by Dr. Jeffrey M. Masters Chief Meteorologist, The Weather Underground, Inc.
In a warmer earth scenario: In a warmer earth scenario
Ocean level will rise because as liquid water is heated it expands.
The ice caps melt and add water to the system.
Slide25: http://www.whoi.edu/institutes/occi/images/occi_abrclimate_jk_lev_en.gif
Sea Ice Concentration: Sea Ice Concentration
Temperature and Ice Accumulation vs. Time: Temperature and Ice Accumulation vs. Time