Global Climate Flashcards
What is an open system?
An open system exchanges matter and energy with its surroundings. eg. the atmosphere
What is a closed system?
A closed system exchanges energy but not matter with its surroundings.
What is an isolated system?
An isolated system exchanges neither energy nor matter with its surroundings.
What is a negative feedback loops?
This promotes stability in a system as it reverses a change and moves the system in the direction of the original state of equilibrium.
Thermosphere
a virtual vacuum
Stratosphere
lacks dust and water vapour
Mesosphere
Temps decrease due to decreasing density that prevents
Risk
Probability of an event causing harm
Vulnerability
The susceptibility of a community to a hazard or to the impacts of the hazard (climate change).
Perception
Opinion/view on climate change.
Resilience
The degree to which people can cope with the impacts of climate change.
Adaptations
Actions that countries will need to take to respond to the impacts of climate change that are already happening, while at the same time preparing for future impacts.
Mitigation
Efforts to reduce emissions and enhance sinks.
Define Energy Balance
The balance between the input of energy (solar insolation/SW radiation) and output of energy (terrestrial radiation/LW radiation)
What is the Earth’s energy budget?
- Incoming solar/SW radiation
- Some reaches Earth’s surface
- Earth’s surface re-emits terrestrial/LW radiation
- Some absorbed/trapped by greenhouse gases.
What are examples of Greenhouse gases?
Carbon dioxide
water vapour
methane
What is a changing balance due to?
- Changes in solar radiation including: global dimming, global brightening, sunspots, Earth’s orbit and Earth’s tilt
- Changes in Earth’s Albedo
What is global dimming?
Air pollution produces greenhouse gases
Solar radiation bounces off atmosphere
Volcanic eruptions - releases ash particles, gas which prevents the path of the solar insolation to reach the Earth
What is global brightening?
Changes in cloud cover, destruction of ozone layer so more solar radiation enters the atmosphere.
What is Earth’s orbit?
Variation in shape of the orbit.
From circular to elliptical.
Occurs over a period of 1000 years.
Elliptical orbit causes the Earth to move closer or further away from the sun, leading to either an increase or decrease in the amount of solar energy reaching the Earth.
What is the Earth’s tilt?
Earth rotates on its axis making one rotation every 24 hours.
Axis is tilted at an angle of 23.5 degrees away from the sun.
Axial tilt can vary. Either 1 degree towards or away from the sun, changing the amount of solar radiation reaching the Earth.
What is Albedo?
Amount of incoming solar energy reflected back into the atmosphere by the Earth’s surface.
What is high albedo?
More reflective, causes cooling
e.g. snow, removal of vegetation
What is low albedo?
Less reflective, causes warming
e.g. asphalt
What is a positive feedback loop?
This type of feedback amplifies a change in a system and keeps it going in the same direction. So a small disturbance in the system causes an increase in that disturbance.
Product of a reaction leads to an increase in that reaction.
Give an example of a high albedo positive feedback loop
Lighter surface
Higher albedo
Less solar radiation absorbed
Cooling
Ice sheets extend
(link back to lighter surface)
Give an example of a low albedo positive feedback loop
Darker surface
Lower albedo
More solar radiation absorbed
Warming
Ice sheets melt
Soil exposed
(link back to darker surface)
What is the natural greenhouse effect?
When GH gases allow SW radiation from the sun to pass through the atmosphere but trap an increasing proportion of outgoing LW radiation from the Earth.
This trapping of energy in the atmosphere by GH gases is essentially the GH effect which keeps the atmosphere warm.
What is the enhanced greenhouse effect?
- Anthropogenic release of GH gases.
Burning fossil fuels for energy, transports. Deforestation.
