April 8th lecture Flashcards
What is the “Day after Tomorrow” Premises?
- It is the idea that global warming will lead to an abrupt climate change occurrence over several days/weeks
What would happen in a “Day after tomorrow” situation?
- Start of a new ice age and ice sheet covering much of north america
- Giant hurricanes from arctic freezing people with -150F temperatures
- Massive 40ft tall strom surges
- extreme weather globally
Can the oceanic conveyor be shut down?
No, but it can be weakened.
Is it likely that the oceanic conveyor will shutdown today?Why?
No
What evadance do we have that the oceanic convener will not shut down
- As the last ice age ended and climate warmed, the ice cap started to melt - This formed a large freshwater lake, Lage Agassiz, around where the Great Lakes presently are
What dose lake Agassiz have to do with oceanic shutdown predictions
Large amounts of water from this lake began to drain into the north Atlantic ocean
What happens when you a mix large amounts of fresh water with the ocean in the North Atlantic?
- Surface density drops
- No more deep sinking
- Weakening of the conveyor
What happens when the oceanic convector is weakened?
The return floe of water to the north ( and thus heat ) was weakened
What happened to cause the oceanic conveyor to return back to normal?
- all the fresh water is mixed into the ocean, and cold temperatures allow for convection to start again.
What are 4 steps of oceanic variability impacting Greenland glaciers? ( HARD, LONG< WILL SUCK)
1) Sub-Polar Gyre Circulation impacted by the
North Atlantic Oscillation
• 2) Changes transport of warm salty water within
gyre, to west coast of Greenland
• 3) Changed winds also drive this water onshore,
into Greenland Fjords
• 4) Added heat in deep waters of fjord impacts and
leads to rapid glacier melt
