The Atmosphere - Physical Flashcards
What is nuclear fusion?
Sun releases energy in the form of electromagnetic radiation. The reactions involve joining the hydrogen atoms to produce helium + a neutron.
What is insolation?
Solar radiation reaching the Earth’s surface.
What is a dynamic equilibrium?
There is a balance between the amount of radiation that reaches the earth and that which leaves it.
Description and Importance of UV radiation.
Mostly absorbed by ozone. Prevents relatively high frequency radiation reaching the surface which could lead to skin cancer. UVA stimulates production of vitamin D in humans.
Description and importance of visible radiation/light.
Converted to chemical energy. In photosynthesis, molecule of water split with light energy.
Essential for reactions that take place in photosynthesis to occur.
Description and importance of infrared and visible.
Converted to heat energy. Levels of solar exposure between surface water and deeper parts leads to different water layers having different temperatures.
What are the likely causes and effects of global climate change on sea levels and ocean acidity?
- Kinetic energy in water increases, therefore occupies higher volume = thermal expansion.
- Glaciers melt into water adding additional water to sea.
- Sea levels rise 3mm per year.
- Oceans are alkaline. CO2 dissolved in water is acidic. This means ocean pH levels could become less alkaline, affecting many ocean organisms.
What are the likely causes and effects of global climate change on weather patterns?
-Higher temperatures lead to increased evaporation and precipitation.
- Areas that previously received rain may get less if too warm for water vapour to condense. Prevents farming.
- Changes in frequency and velocity of winds = increased storms/damage.
What are the likely causes and effects of global climate change on the cryosphere?
- Glacier movement: Meltwater causes glaciers to move quicker.
- Ice lakes: Water collected can create a lake which could lead to flooding.
- Reduced ice and snow cover: Increased temperatures reduce snow and the surface albedo.
- Loss of ice shelves: Form icebergs when they break.
What are the likely causes and effects of global climate change on the ocean circulation?
North Atlantic Current / Gulf Stream.
1) Water heats up in Gulf of Mexico.
2) Moves to North West.
3) Delivers warm water to Europe.
4) Water cools, more dense so drops.
5) This pulls more water from the Gulf.
Climate change could melt Greenland ice, reducing salinity (so density decreases) of water - falling of water at North wouldn’t happen. (A theory)/
What is El Nino?
Normally westward wind causes cold, nutrient rich waters to be drawn up near the coast of South America.
This can influence rainfall patterns.
In some years the winds creating the surface currents change direction. This can lead to a drop in rainfall in Eastern Australia, a loss of nutrient rich waters in South America as well as heavy rains and floods.
How is the Adelie Penguin being threatened by climate change?
Antarctic sea ice retreating due to increased global temperatures. Their food source (krill) is falling. They have to spend more energy hunting, less energy breeding and raising young.
How is the Golden Toad being threatened by climate change?
Drought and fungus and other climatic conditions killed them. They are extinct.
How is the sea turtle being threatened by climate change?
The beaches they lay eggs on are disappearing due to rising sea levels. Also, nest temperatures determine gender so increase in temperatures means only one gender will be prevalent in the nests.
What are the main ecological changes that may affect a species?
- Habitat loss.
- Food (e.g. competition).
- Temperature.
- Timing of natural events (e.g. early seasons).
- Light.
What are the impacts of climate change on health?
Disease vectors may be able to spread further e.g. mosquitoes.
What are the impacts of climate change on food supplies?
Reduced water availability may increase need for irrigation.
Mild winters may allow pests to survive easier and cause problems in following years.
What are the impacts of climate change on infrastructure?
Road heat stress due to increased temperatures.
Bridge damage.
Why are there often uncertainties in the data collected to show hw the climate has changed?
- Lack of historical data.
- Limited reliability of proxy data.
- Lack of understanding of natural processes that control weather, ocean currents etc.
- Time delay between cause and effect.
What is climate modelling?
Allows the effects of different, connected systems to be estimated.
Data is input from a particular year in the past to see if the model can predict the outcome for a later year.
Why are satellites useful for data collection?
- e.g. cryosat, can be used to collect info on ice cover.
- Low Earth Orbit satellites collect information from whole Earth Surface. Satellites in geostationary orbit collect less detailed info from a constant position. Includes microwaves and IR emissions.
- Can collect data on ice mass with sensors e.g. laster altimeters.
Monitoring ocean currents - Argo Floats.
Measure salinity, temperature, depth in an ocean profile.
Pops to the surface to transmit data - then descend again.
1) Float deployment.
2) Descent to drifting depth.
3) Drift for 10 days.
4) Descent to profiling depth (2000-6000m)
5) Ascent: Measuring all variables.
6) Data transmission.
7) Start next cycle.
What is positive feedback?
Change of an environmental factor causes environmental changes that increase rate of original effect.
What is negative feedback?
Environmental change causes a reduction of the original to re-establish equilibrium
