Midterm 1 long answer questions Flashcards
What are the 4 modes of heat transfer? For each, give an example (in detail) of one animal’s adaptation for controlling heat loss.
Conduction: defusal of heat through temperature gradient. Ravens have knobby, uneven feet which reduces the amount of their foot on contact with the cold ground. Because of this adaptation, the surface area that heat can diffuse out of the foot and into the ground is largely reduced.
Evaporation: Heat exchange through the evaporation of water: Caribou have specialized Conchae that mitigate the amount of water lost (and therefore heat evaporated) from breathing. As the animal breathes in, warm wet mucosa saturate the air with water, as the animal exhales, the warm wet air from the lungs condenses into the now dry mucosa, meaning they exhale cool ‘dry” air.
Radiation: Transfer of energy through electromagnetic waves: Honeybees shiver to produce heat by muscle contraction. The bees gather within the colony in large groups that through shivering, they radiate heat onto each other to stay warm.
Convection: movement of a fluid (water or air) removing or giving heat to the area: Painted turtles move to the bottom of a waterbody in the winter. Since water is more dense at warmer temperatures, the warm water sits at the bottom of the lake/river while the cold water moves to the top.
What are the three definitions of the Arctic? Give specific explanations of how each Milankovitch cycle would affect each of the 3 Arctic definitions.
Geophysicist: the southernmost latitude at which the sun can remain
continuously above or below the horizon for 24 hours
Climatologist – region with mean temp < 10oC in warmest month (July)
Ecologist – region lying north of poleward limit of trees
Eccentricity: would effect the angle of which the sun hits the earth altering the geophysicist definition as the sun would not be able to stay above the horizon at the same latitude in the winter. Would lead to colder summers/winter effecting the growing season and ecologist / climatologist definitions
tilt: Increased tilt leads to higher variability in the seasons, altering the tree line and therefore the ecologist definition. Also would affect average temperatures and the climatologist definition. Also would effect the Geophysicist definition as the angle the sun is hitting the earth as changed.
Procession: The wobbling of the earth would be constantly affecting all of the definitions as it changes the angle and distance from the sun. this would impact the Geophysicist most directedly
