Climate Change With Jeff Lewis Flashcards
What is the agreed upon scientific certainty that humans have influenced climate change?
95%
Weather vs climate?
Weather is the state of the atmosphere at a specific place and time. Unpredictable
Climate is the average weather over a long period of time. The standard averaging period is 30 years. Relatively predictable as it is a trend
Where is the greatest change?
Oceans are warming faster and becoming increasingly acidified
Where is most heat from global warming being absorbed?
Ocean
Why has 2015 shattered temp records
Strong El Niño event paired with average temperature increases.
Positive feedback vs negative feedback?
Positive feedback enhances effects (water vapour and albido of land in Arctic)
Negative feedback reduces effects
Why is the Arctic more effected than Antarctic?
Arctic is an ocean
5 overall main causes that effect climate change
Forcings may be external:
- Changes in solar output
- Changes in orbital parameters
or internal:
- Changes in surface energy balance
- Changes in circulation
- Changes in atmospheric composition
What is some evidence of climate change?
- Observational and satellite data show an increase in global average temperature
- Since 1980, most glaciers have lost mass
- Permafrost is warming and melting in many regions • Snow and ice melt is occurring earlier in the spring
- Sea level is rising
- Arctic sea ice extent is decreasing
- The ocean is becoming more acidic (absorbing more CO 2 )
- The frequency of extreme events is increasing (e.g. floods, droughts, high temperature records, etc.)
How are land use changes effecting climate change?
Deforestation (especially in tropics). Slash and burn. Used to be the dominant practice in Europe.
More reflective ground can reduce warming
Burning of vegetation enhances ghg
How is human contribution so devastating when natural processes produce ghg too?
Because there is no balancing reduction to account for the emmision said of humans that stay in the atmosphere long after use.
Carbon formed over millions of years is burned instantaneously for energy
Impacts on forests
Massive projected shift in BEC zones
Changes in growth rates
- Increased competition from other species more suited to the climate
- New assemblages of species will occur in space and time
- Northward or upslope shifts in terrestrial ecosystems
- Species may be unable to move into areas of suitable climate due to barriers to movement, slow migration rates, unsuitable growing substrate or lack of habitat
- Coastal forests will likely see an increase in the number and intensity of storms, thereby increasing windthrow damage
How are land use changes effecting climate change?
Deforestation (especially in tropics). Slash and burn. Used to be the dominant practice in Europe.
More reflective ground can reduce warming
Burning of vegetation enhances ghg
How is human contribution so devastating when natural processes produce ghg too?
Because there is no balancing reduction to account for the emmision said of humans that stay in the atmosphere long after use.
Carbon formed over millions of years is burned instantaneously for energy
Impacts on forests
Massive projected shift in BEC zones
Changes in growth rates
- Increased competition from other species more suited to the climate
- New assemblages of species will occur in space and time
- Northward or upslope shifts in terrestrial ecosystems
- Species may be unable to move into areas of suitable climate due to barriers to movement, slow migration rates, unsuitable growing substrate or lack of habitat
- Coastal forests will likely see an increase in the number and intensity of storms, thereby increasing windthrow damage
