Chapter 10: Climate - Past, Present, Future

Question 1

What is climate?

Answer 1

The climate is weather averaged over time. Climate fluctuates with time and is influenced by a number of factors, including human activity

Question 2

What form of energy does the sun emit?

Answer 2

shortwave electromagnetic radiation

Question 3

How is the heat emitted by the earth?

Answer 3

longwave infrared radiation

Question 4

How much heat is emitted by the Earth?

Answer 4

the Earth emits enough heat to warm it up to -1 degree Fahrenheit

Question 5

Why is the global mean surface temp much warmer than earths baseline of -1?

Answer 5

due to the greenhouse effect

Question 6

Greenhouse effect

Answer 6

the presence of gases in our atmosphere that insulates the Earth like a blanket, trapping the longwave radiation emanating out from the Earth’s surface. Promote warming of the atmosphere

Question 7

What are the natural human-made atmospheric gases that are causing the greenhouse effect? And what do these gases do?

Answer 7

– Water vapor: H2O
– Carbon dioxide: CO2
– Methane: CH4
– Nitrogen oxides: NOx
– Chlorofluorocarbons: CFCs
These gases trap heat and warm the lower atmosphere, similar to the effect of the trapping of solar heat by a greenhouse.

Question 8

What is the Paris Climate Accord trying to do?

Answer 8

it is trying to limit global temperatures from rising any higher than 2 degrees celsius.

Question 9

Shrinking of polar ice caps and melting

Answer 9

The rapid decline in the size of the polar ice caps in recent years is partly due to atmospheric circulation that has favored melting. The melting induces a positive feedback cycle warming leads to more warming which is exacerbated at higher latitudes and elevations.

Question 10

Permafrost

Answer 10

permanently frozen ground, seen in northern latitudes above 60 degrees, underlying 20% of the land area in the world.

Question 11

What happens when there is changes in permafrost?

Answer 11

changes affect the distribution of surface water and groundwater.

Question 12

Where is the heat of absorbed by the earth stored?

Answer 12

The oceans store and transport a tremendous amount of heat around the globe. Much of the heat absorbed by the earth is stored in the oceans.

Question 13

What causes hurricanes of greater intensity?

Answer 13

the increased heat supplies energy which spawn hurricanes

Question 14

Thermohaline Circulation

Answer 14

(heat salt) the roles of temperature and salinity in moving water around the globe

Question 15

Ocean conveyor belt

Answer 15

Global circulation of ocean waters contributes to the change.

Question 16

What size belt is the Gulf Stream a part of?

Answer 16

is part of this larger belt of the ocean conveyer belt, whereby water surface water is transported east and north to Greenland, where it cools from contact with cold Canadian air.

Question 17

Downwelling

Answer 17

as water cools, it increases in density and sinks to the bottom

Question 18

Upwelling

Answer 18

where the water heats up and rises to the surface

Question 19

What are the benefits of upwelling?

Answer 19

Water is nutrient-rich, and where upwelling occurs diverse aquatic ecosystems grow and thrive.

Question 20

What is El Nino?

Answer 20

the periodic halt in upwelling, the fertile cold waters no longer rise up along the western south american coasts. It is part of a larger decade-long cycle where el nino is a warm phase and la nina is the cold phase

Question 21

What is the result of the El Nino?

Answer 21

the event causes large scale changes in the pathways, frequency, and intensity of Pacific storms and timing of the monsoon season

Question 22

What is the result of warmer waters?

Answer 22

reduces the productivity of the primary producers: phytoplankton, microscopic photosynthetic marine algae that form the base of many ecological food webs

Question 23

CO2 and the Ocean

Answer 23

Oceans can absorb CO2 and thus helps slow the rate of global warming, CO2 levels are building up in the ocean, causing them to be more acidic

Question 24

What was used to predict past global temperatures?

Answer 24

the abundance of oxygen 18 and oxygen 16

during ice ages, the ratio would be larger because ocean water would be enriched in Oxygen 18 and Oxygen 16 would be trapped in ice caps. Microorganisms making their shells during this cooler time would have higher concentrations of Oxygen 18

Question 25

Albedo

Answer 25

glaciers white in color reduce global warming by reflecting sunlight back into outer space

Question 26

Positive feedback cycle of climate

Answer 26

the warming trend reinforces itself, the more the glaciers retreat, the lower the albedo, and the more quickly earth warms up.

Question 27

Negative feedback of climate

Answer 27

the warming induces changes that encourage the opposite (in this case cooling), due to large scale storms being more frequent