Lecture 32 Flashcards
Anthropogenic caused climate change is driven by
accelerating global population growth and the ecological footprint of each human being on the limited resources that the earth provides.
Deforestation impacts:
soil stability, water cycle, and biogeochemical reactions
Humans have replaced natural vegetation with _____ with fewer ____
managed landscapes with less biodiversity
While ___ million HA of forest are added, ___ million HA are lost
5.2 added and 14.6 lost
over ___ of marine fish stocks are fully fished or over-fished
80%
Why fishing is a concern
FIsh nets capture non-target species (dolphins) or damage seafloor habitats during net dragging from large ships
Coral Reefs
colonies of tiny animals coexisting with photosynthetic algae called zooxanthellae (which provides food by photosynthesizing)
Coral Bleaching
When sediments from soil erosion inhibit photosynthesis, and the zooxanthellae algae are expelled/die. Ocean acidification contributes to the death of corals, as CO2 forms carbonic acid which makes it more difficult for carbonate shell-forming organisms to build their shells, making them more susceptible to predation.
Since 2016, ___ of all the corals in the Great Barrier Reef has died due to the influx of ______.
half, due to unusually warm water
The rate of extinction is currently:
thousand per decade
We are in the midst of a ___ great extinction
6th
Concern with CO2, CH4, and N2O
the impact they have on the absorption of outgoing heat from the Earth - as they are radioactively reactive (absorb heat and raise the temperature of the atmosphere)
Within 200 years we have increased atmospheric carbon levels by ____
50%
It was estimated that ___ of Carbon was added to the atmosphere by the fossil fuel industry and ___ by land-use changes
10 gigatons and 1.8 gigatons
Radiative forcing
the influence that a factor has on incoming radiation to the earth
Methane has a ___ radiative forcing than carbon dioxide
stronger (x4)
We receive an increased ___ watts of energy per square meter at the surface
1.6 watts
The global temperature change has increased by ___ in the past 150 years
0.5-0.8 degrees
Clear changes over the past 150 years due to climate models
average global temperatures have increased, the extent of sea level has risen by nearly 20 cm, precipitation patterns have changed dramatically
