Global Warming Flashcards
What is long term climate change
Change over tens and hundreds of thousands of years. Including ice ages
What causes long term?
Sun’s orbit
Sun spot
Volcanic activity
Tectonic plates
How de we know about long term
Ice cores
Ocean sediments
Pollen analysis
How do ice cores work?
You extract a large tube of glacial ice. We can see different layers which are different years and analyse the levels of each gas.
Ocean sediments
Drill a hole and take a tube of the oceans floor, with layers. They can see what type of rock and what animals lived there so they can guess how the temperature was
Pollen analysis
To see what vegetation was in the past so can have a guess on how the temperature was
What is medium term climate change
The last couple of thousand of years.
What causes medium term?
Variations on solar output
Volcanic activity
How do we know about medium term?
Historical records
Tree rings
Written accounts
Historical records
Maybe describe temperatures in those times which help us have a brief idea
Written accounts and paintings
We know because it is described. Maybe the temperature is drawn.
Tree rings
Thick ring: warm period
Thin ring: cold period
(Each ring is one year)
What is short term climate change
Refers to the last hundred years. In this period the changes have changed much more quickly and produced drastic results
What causes short term?
Human activity Burning fossil fuels Deforestation Agriculture Waste disposal
How do we know about short term
Weather stations
Photographs
Sea level rise
Weather station
Measure detailed data and statistics
Sea level rise
The sea level and the temperature give an indication of global climate change
Photographs
We can see sometimes the atmosphere, animals and vegetation.
What is the natural greenhouse effect
Greenhouse gases have acted as the world’s insulation in natural process called the greenhouse effect. The solar radiation(uv) passes through these to get to the earth’s surface were some is absorbed and some is reflected back. The energy that is absorbed by the earth is converted into heat and emitted back into the past atmosphere as infrared radiation. This heat is trapped by greenhouse gases and gets trapped in between the earth’s surface and the atmosphere and heats up the temperature.
What is the enhanced greenhouse effect
The unnatural greenhouse gas emissions as a result from human activity. More infrared radiation is trapped inside and heats up the temperature more
What activities are causing the enhanced greenhouse effect
Deforestation
Burning fossil fuels
Cows
Landfills
Burning fossil fuels
When these are burnt, they release co2
Deforestation
To clear land for agriculture, they chop down the trees who release the co2 stored in them
Cows
These produce lots of methan as part of their digestive process. The number of these are increasing so the level of this gas also increases
