Or qualify (ex. Possible but not the way it is done in the film) / Actual Cause/Explanation with source of information
40 Ft. swell/wave hitting Manhattan / Not Realistic as portrayed in film. / No wave can grow this large without breaking, says NASA oceanographer David Adamec.
http://www.usatoday.com/weather/resources/climate/2004-05-27-day-after-science_x.htm
Dozens of tornadoes forming all at once and joining together.? / They lose strength over land, and when the air or water temperature falls below tropical levels. Hurricanes cannot form in the Arctic. In addition, no storm could grow large enough to cover the entire northern hemisphere
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=9948
Tsunami reach
New york from an ice sheet collapse in antartica? / Many landmasses in the southern hemisphere would likely block any tsunami originating in Antarctica from reaching New York. Ice shelves
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=9948
Can the world change temperatures that fast? / The ocean, because of its immense volume and the slow rate at which it gains and loses heat, cannot physically change as quickly as depicted in the movie.
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=9948
Can the northern hemisphere be covered with a storm for that long? / No, hurricanes can not stay on land for that long because they get there energy from the oceans warm temperatures.
And since the storm is -150 degrees, it would die in less than an hour in the ocean.
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=9948
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