Climate Change

Question 1

The average surface temperature of the Earth has increased by how much in the last century?

Answer 1

Over 1.1 degree celceus

More than half of the increase happened after 1970.

Question 2

What is Polar amplification:?

Answer 2

Climate change is more extreme in polar regions than in other regions.
The Arctic is heating faster than other regions.
The pattern of warming in the Antarctic is complex.

Question 3

Surface temperature is controlled by?

Answer 3

• Insolation
• Albedo
• Greenhouse effect Changing any one of these will change the temperature.

Question 4

Insolation?

Answer 4

Incoming solar energy

Question 5

Albedo?

Answer 5

Energy is reflected back to space without warming the surface

Question 6

Greenhouse effect?

Answer 6

Gases in the atmosphere absorb and re-radiate energy

Question 7

There are many greenhouse gases.

The main natural greenhouse gases are?

Answer 7

• H2O (water vapour)
• CO2 (carbon dioxide)
• CH4 (methane)
• N2O (nitrous oxide)
• O3 (ozone)

Question 8

In addition to greenhouse gases, we also emit sulphate aerosols, what effect does it have?

Answer 8

A cooling effect by increasing the albedo (reflectance).

Question 9

How does volcanoes affect the climate?

Answer 9

By releasing CO2 and sulfate (SO2). Sulfates have a short-term cooling effect.

Question 10

What are General Circulation Models (GCMs) ?

Answer 10

Complex computer models, used to calculate the combined effects of natural and anthropogenic factors.

Question 11

What is all of the global warming in the last 50 years due to?

Answer 11

Anthropogenic factors.

Question 12

What are the main sources and sinks of anthropogenic CO2?

Answer 12

90% is from fossil fuels and cement
10% is from land use (mostly deforestation)
-
24% dissolves into the ocean Causes acidification
28% is absorbed by land plants Increases terrestrial GPP
48% stays in the atmosphere Causes global warming

Question 13

What is Climate sensitivity? And what is a good measurement?

Answer 13

How much the climate warms in response to a change in any climate forcing.
A good measure of the sensitivity to CO2 is how much warming is caused by doubling the atmospheric CO2.

Question 14

Why is the climate system so complex? And tipping point?

Answer 14

It has both positive (amplifying) and negative (dampening) feedbacks.

The Earth system may have tipping points, where the system suddenly shifts into a different state.

Question 15

What does it mean that changing the average temperature also changes the extremes?

Answer 15

Extremely hot weather is becoming hotter and more frequent. (small change in averages, big changes in extremes)

Question 16

What has happen to Global NPP? (net energy available after respiration)
Net Primary Productivity (NPP) maps the net amount of solar energy converted to plant organic matter through photosynthesis.

Answer 16

It has increased globally.
Most of the increase is in boreal and tropical forests.
NPP decreased in tropical savannas and temperate forests.

Question 17

How much have the sea level risen?

Answer 17

25 cm.

Question 18

What is coral bleaching?

Answer 18

When the symbiotic alige living nsde the coral die, they are very sensitive to heat stress.

Question 19

What is the consequences of carbon dioxide dissolving into the ocean? (its effect on shelled invertebrates?)

Answer 19

Makes it more acidic and can disrupt food webs.

Ocean acidification decreases the calcification of shelled invertebrates.

Question 20

What does future global warming depends on?

Answer 20

Human actions
1) CO2 emissions
2) Land use
• Climate sensitivity

Question 21

Geoengineering involves large-scale projects to modify Earth’s energy balance by?

Answer 21

• Removing CO2 from the atmosphere

* Reflecting solar energy (increasing albedo)