Answer to Question 1
The percent of radiation reflected from a given surface is the albedo. Snow has one of the highest albedo percentages, in that up to 95 of sunlight may be reflected from the snow surface. If total snow cover on Earth is reduced, the energy that would have been reflected becomes absorbed instead. Increased polar snow and ice melt will result in higher sea levels, which coupled with rising ocean temperatures will cause an increase in evaporation rates that will add more water vapor (a greenhouse gas) to the atmosphere and, subsequently, increase the amount of radiation returned to Earth.
Answer to Question 2
A variety of factors must come together in order to produce a tornado. Once this happens, tornadoes usually progress through a series of stages. The first stage is the dust-whirl stage, where dust swirling upward from surface marks the tornado's circulation on the ground and a short funnel cloud often extends downward from the thunderstorm's base. Damage during this stage is normally light. The second stage is the mature stage, when the tornado's strength increases. This is the stage when damage is normally most severe as the funnel reaches its greatest width and is almost vertical. The final stage is the decay stage, where the tornado is typically stretched into the shape of a rope, usually becoming greatly distorted before it finally dissipates.