Lecture 7: Energy, Climate, and Weather

Question 1

What is the jet stream?

Answer 1

An area of very fast air movement (wind) in the upper atmosphere

Question 2

What is weather vs climate?

Answer 2

Weather is day-day (or hour-hour) changes in atmospheric conditions, whereas climate is the long-term averaged weather for an area.
“Weather is your mood, climate is your personality.”

Question 3

What determines global climate?

Answer 3

Energy received from solar radiation & precipitation.

Question 4

How is climate affected by spatial variability?

Answer 4

Uneven heating of the spheric surface of the globe drives transfer of energy from surplus regions to deficit regions.

Question 5

How is climate affected by temporal variability?

Answer 5

the more an object faces the sun, the more energy it receives and due to the earths tilted axis, certain areas on earth spend more time facing the sun (southern hemisphere).

Question 6

What are climatic oscillations?

Answer 6

Any reoccurring global/regional climate pattern (temperature, precipitation, air pressure…)

Question 7

What does ENSO stand for?

Answer 7

El-Nino-Southern Oscillation

Question 8

What is ENSO?

Answer 8

Cyclic variations in the sea surface temperatures and convection cells in the equatorial region of the pacific ocean.

Question 9

What is upwelling?

Answer 9

Surface water being moved westward is replaced by colder water from deeper in the ocean.

Question 10

What is El Nino?

Answer 10

Warm surface winds shifting eastward towards South America.

Question 11

How does El Nino affect climate?

Answer 11

Warmer waters shift the jet stream closer to the equator:
- some areas become wetter/dryer
- reduced monsoons in Asia
- less nutrients off the coast of South America means fish populations decline or migrate (due to less upwelling)

Question 12

What is La Nina?

Answer 12

The opposite of El Nino: the cooling of sea surface temperatures intensify the “normal” climatic patterns.

Question 13

How does La Nina affect climate?

Answer 13

Colder waters shift the jet stream northwards:
- the opposite regions between wetter/dryer
- more nutrients to support South American fish (populations increase) (due to more upwelling)
- more monsoons in Asia
- more severe Atlantic hurricane season

Question 14

What is the feedback loop within ENSO?

Answer 14

High surface sea temperatures move westward, bringing western pacific atmospheric convection, which causes westward surface winds to increase, thus increasing westward surface ocean currents, which push the high surface sea temperatures more westward.

Question 15

What causes the shift between El Nino seasons and La Nina seasons?

Answer 15

We don’t know.

Question 16

What are other regional climate forcings?

Answer 16

• Buffering effects of water
• Ocean currents
• Urban heat island effect
• Topography
• Vegetation

Question 17

What is the buffering effect of water?

Answer 17

Water has a high specific heat capacity so it can hold more energy and takes longer to release this energy than land.

Question 18

How does the buffering effect of water affect climates?

Answer 18

Coastal areas maintain a more even temperature throughout the year because water maintains its temperature better than land does.

Question 19

How does the buffering effect of water affect air movement?

Answer 19

During the day, the land heats up faster than water, so air moves upwards and is replaced by air flowing in from the ocean.
At night, the land cools faster and warmer air above the ocean rises, bringing in cooler air from the land to replace it.

Question 20

How do surface currents transport energy?

Answer 20

Warmer water at the equator is transported to colder regions closer to the poles.

Question 21

What is the gulf stream?

Answer 21

A surface current that begins at the equator and travels along the eastern coast of north america towards northwest europe. (for ex: why London winters are much warmer than Calgary winters even though they’re at the same latitude).

Question 22

How does topography (mountains) affect climate?

Answer 22

sea water evaporates up a mountain and as it rises, it cools and rain falls. The cold dry air then flows down the far side of the mountain where it warms up as it falls, but maintains its dryness (causing deserts). (Ex: rainforests on the coast of BC are separated by the rockies from the dryer “desserts” in AB)

Question 23

What is the urban heat island effect?

Answer 23

Low albedo in man-made surfaces absorb more solar radiation than natural surfaces: increasing temperatures in urban areas.

Question 24

What are flying rivers?

Answer 24

A system which brings moisture over large areas as a result of wind currents and plant transpiration.

Question 25

How do plants affect flying rivers?

Answer 25

Precipitation that falls to the earth is released back into the atmosphere via plant transpiration. When enough plants are in one location, the volume of water released can be signifcant enough to move over vast distances.

Question 26

What is cloud seeding?

Answer 26

Certain plants release chemicals which function to intentionally increase cloud formation. If enough of these plants are in one place, possible cloud production and precipitation is common.