Climate Change

Created by

Hasset Kifle

Cards (49)

What is climate change?
Climate change is the long-term shift in the planet's weather patterns or average temperatures
Evidence for climate change
-average global temps
-Ice cores
-Shrinking glaciers
-Seasonal glaciers
-Rising sea levels
What is the quaternary period 
The most recent geological time period, spanning from about 2.6 million years ago to the present day where temperatures have fluctuated a great deal
4 effects of global climate change
-many of the worlds glaciers and ice caps are sinking
-low lying Pacific islands (Tuvalu and Maldives) are under threat from rising sea levels
-sea levels may rise by 1m by 2100 flooding agricultural land ( Bangladesh, Vietnam, India)
-arctic sea ice is less extensive than in the past
explain rising sea levels 
The average global sea levels has risen between 10 and 20cm in the past 100 years
How do sea levels rise
When temperatures rise, freshwater ice melts resulting in more water in seas
When ocean water warms it expands in volume- thermal expansion
Explain seasonal changes 
The timing of natural seasonal activities such as tree flowering and bird migration is advancing
Example of a seasonal change 
A study showed that bird nesting in mid 1900s discovered that 65 species nested on average of 9days earlier
Explain shrinking glaciers and melting ice
Glaciers throughout the world are shrinking and retreating
Example of shrinking glaciers and melting ice (arctic sea ice)
Arctic sea ice has thinned by 65% since 1975 and in 2014 it's extent was at an all time low
What is happening to the arctic sea ice
Arctic sea ice is less extensive than in the past affecting wildlife such as polar bears. This may provide opportunities for ships to use the North West Passage in the future
What are ice cores 
Cylinders of ice drilled out of an ice sheet or glacier
How can scientists use ice cores to tell them what the global temperatures were like in the past
Scientists can study the oxygen in ocean sediments and water molecules in ice to calculate the temperature
What are the three main natural causes of climate change
orbital changes, solar activity, volcanic activity
What are orbital changes also called
Milankovitch cycles
What is eccentricity?
Varies from a circular to elliptical orbit which happens every 90,000-100,000 years
What is axial tilt?
The tilt of the earth axis moves back and forth between 21.5 and 24.5 every 41,000 years
What is a precession of the Earth? 
A slow change or wobble in the orientation of the Earth axis over a period of 26,000 years
What are the short term impacts of volcanic activity
Block out sun, reducing temperatures on Earth
What are the long term impacts of volcanic activity
Sulphur dioxide is released from volcano which converts to sulphuric acid which acts like a mirrors reflecting radiation from sun which over many years will also reduce temperatures
Example of volcanic activity (1991) 
Mt. Pinatubo, 1991
Earths surface cooled for 3years after eruption by as much as 1.3degree
Example of volcanic activity (1816) 
Mt Tambora, Indonesia 1816
Most powerful eruption in the world for 1600years
Average temps fell by 0.4-0.7degrees
Impacts of volcanic activity
-radiation from suns is reflected so doesn't reach earth
-global temperatures fall
-crop failure therefore famines, health issues from ash, distress etc
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What is the natural green house effect 
The greenhouse effect keeps the Earth naturally warm enough to support life
What is the difference between enhanced greenhouse effect and natural greenhouse effect
The enhanced greenhouse effect is due to human activities which has increased the amounts of greenhouse gases but the natural,greenhouse effect keeps the earth naturally warm
How much carbon dioxide accounts for the enhanced green house effect
60%
Where does carbon dioxide get released
Car exhausts
Deforestation
Burning wood
Burning fossil fuels
How much methane accounts for the enhanced greenhouse effect 
20%
How is methane released?
Farm livestock
Rice farming
Burning biomass for energy
Decaying organic matter in landfill sites and compost sites
How effective is nitrous oxide in capturing heat then co2
Very small concentrations are up to 300times more effective
How does nitrous oxide get released
Car exhausts
Sewage treatment
Agricultural fertilisers
Power stations
What are the 4ways climate change can be managed
Alternative energy sources
Carbon capture and storage
Planting trees
International agreements
What is a sunspot? 
A dark patch on the surface of the sun which produces heat
How do sunspots effect temperatures on Earth
The amount of radiation emitted by the sun fluctuates. High levels of radiation easily to an increase in earths temperatures
The burning of fossil fuels accounts for how much of the carbon dioxide emissions 
87%
What are the alternative energy sources
Wind, water, geothermal, nuclear, biomass, solar, tides
Explain the process of carbon capture and storage
The process of 'carbon capture and storage' is when carbon molecules are captured, compressed, piped and injected as a liquid to a well underground to be stored in a suitable geological reservoir
How do trees remove Co2 from the atmosphere
photosynthesis
How does planting trees reduce climate change?
Trees release moisture into the atmosphere which produces more cloud, reducing solar radiation producing a cooling effect
Trees also absorb Co2
First international agreement
Kyoto Protocol (2005)
Countries agreed to reduce carbon emissions by 5.2% by 2012
USA and Australia didn't sign- two of the biggest emitters of carbon which meant the agreement wasn't very helpful