Unit 2 - Global Climate Flashcards
Natural Greenhouse Effect
Natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by GHGs.
Enhanced Greenhouse Effect
Impact of increasing levels of GHGs in the atmosphere as a result of human activity.
Often referred to as “global warming”.
Global Climate Change
The change in global patterns of climate - precipitation temperatures, winds and pressure systems.
Enhanced GHE vs. Global CC
GCC can relate to any aspect of climate change whereas Enhanced GHE specifically impacts upon temperature.
GCC can have natural causes, EGHE is anthropogenic (caused by human activity).
Energy Balance
How the incoming energy from the Sun is used and returned to space.
If incoming = outcoming then temperature remains constant.
Insolation
Incoming solar radiation.
Positive Feedback Loop
Enhances or amplifies changes; a small change will cause a “snowball effect”. This tends to move a system away from its equilibrium state, making it more unstable.
Eg. Permafrost thawing, melting of ice caps which releases more methane, which increases temperature, which melts even more permafrost etc.
Negative Feedback Loop
Dampens changes; a change in conditions will cause another change which will return conditions to their initial state. Tends to hold a system to some equilibrium state, making it more stable.
Eg. global dimming by volcanic eruptions.
Planetary albedo
The fraction of light reflected from a body or surface. The higher the albedo, the higher radiation amounts reflected.
Albedo = higher on lighter surfaces
What wavelength (long or short) is incoming vs outgoing radiation respectively?
Incoming: shortwave
Outgoing: longwave
Hydrosphere
All the waters on the Earth’s surface, eg. lakes and seas.
Atmosphere
Thin layer of gases that surrounds the Earth.
Biosphere
The parts of the land, sea and atmosphere in which organisms are able to live.
Disparity
A lack of similarity or equality.
Vulnerability
Refers to the degree to which people are susceptible to, or unable to cope with, the adverse impacts of climate change.
Exposure
The degree to which people are exposed to climate change.
Sensitivity
The degree to which they could be harmed by exposure to climate change.
Risk
Expressed as: the likelihood of loss of life, injury or destruction and damage from a disaster in a given period of time.
Risk perception
Refers to people’s subjective judgments about the likelihood of negative occurrences such as injury, illness, disease and death.
Adaptive capacity
The degree to which they could mitigate the potential harm by taking action to reduce their exposure or sensitivity.
Adaptation
Measures based on reducing vulnerability to the effects of climate change.
Eg. Building floating hospitals
Mitigation
Actions that are taken to reduce and curb the potential future impacts of climate change.
Eg. by reducing GHG emissions.
Carbon Sink
A natural or artificial reservoir that absorbs and stores the atmosphere’s carbon with physical and biological mechanisms.
