Anthropogenic Climate change Flashcards
What are the 3 sources of evidence for climate change?
Air, land, and water
What is an anomaly?
The difference in temperature from the ‘normal’ level
What is the normal level?
The long-term average temperature, typically calculated using data from 1961-1990
How have cold and hot temperatures extremes changed?
Both cold and hot extremes are increasing in temperature?
Which warms faster, land or oceans?
Land temperature increase faster than ocean temperature due to differences in heat capacity
How much have annual minimum temperatures on land increased compared to global sea-surface temperatures since the 1960s?
Annual minimum temperatures on land have increased about three times more than global sea-surface temperatures since the 1960s
What three measurements are used to describe a heatwave?
Intensity, duration and number of days
Is a heatwave an example of weather or climate?
A heatwave is an example of weather. A longer-term change in heatwave frequency/intensity/duration is evidence of climate change.
How have terrestrial species’ geographic ranges shifted since the mid-20th century?
Most documented is a poleward/upslope transition
What are 2 impacts of higher surface water temperature in lakes?
- Algal blooms
-Restricting habitats
During what years did the rate of ocean surface temperature warming accelerate?
2010-2019
What happens to the Pacific upwelling along the Peruvian coast during El Nino?
It ceases
What is El Nino?
A natural, irregular phenomenon that is not caused by climate change - often coincides with the hottest years on record
What is the global mean sea level (GMSL) increase form 1901-1990
1.4 mm per year
What is the GMSL increase from 1993-2015?
3.2 mm per year
List three causes for the rising global mean sea level
- Increasing rates of ice loss from Greenland and Antarctic ice sheets
- Continued glacier mass loss
- Ocean thermal expansion
Describe three characteristics of the Artic sea ice from 1979-2019
- The artic sea ice has decreased in size for all months, , and coincides with earlier surface melt onset, later freeze-up, and a longer ice retreat and open water period.
What is albedo?
A measure of the reflectivity of a surface
How does albedo relate to a cooling effect?
High albedo (like snow and ice) results in the reflection of radiation, leading to a cooling effect. This cooling causes more snow, further increasing albedo, and creating a positive feedback loop.
What is unique about the Antarctic compared to the Artic?
The Antarctic has more internal variability than the Arctic because it has no land barriers, the ice is thinner, and is more isolated due to the Antarctic Circumpolar Current.
What trend has been observed in glaciers worldwide since the 2nd half of the 19th Century?
Glaciers worldwide have retreated, with mass loss increasing since the 1970s. This is highly unusual in the context of the last 2,000 years.
When did substantial reductions in spring snow cover in the Northern Hemisphere begin?
1978
How has precipitation changed globally since the middle of the 20th century?
Globally averaged land precipitation has likely increased since the middle of the 20th century, with faster increases since the 1980s.
What is a driver of drought, aside from observed trends in precipitation?
Land use and water management changes are drivers of drought.
