Climate Change
Concepts
Global consequences
Social
We are currently in a interglacial period which are temperature spikes in-between glacial periods. However present global temperatures remain unnaturally high and fluctuating.
Environmental
Economic
Impacts
Natural
Anthropogenic
Deforestation
Fossil fuels
Sun spot activity
Volcanic eruptions
Milankovitch cycles
Milankovitch cycles are changes in the shape of the earth's orbit causing surface temperatures on the earth to increase or decrease due to a change in distance or exposure
Large volcanic eruptions can produce enough sulphur dioxide gas and ash to create a reflective layer in the atmosphere reducing the amount of solar radiation that reaches the earth. This can temporarily decrease local / global temperatures
The sun's output is not constant and solar radiation can be produced at a higher or lower rate. Sun spots show that the sun is more active causing in increase in atmospheric temperatures for a period of time
Causes
Effects
Causes
Effects
Ozone depletion
Changes to the carbon cycle
Contributes to the enhanced greenhouse effect
Demand for resources
Space
Logging industry
Mining
Agriculture / cattle ranching
Housing
Data
Proxy indicators
Ice cores
Dendrachronology
Paintings / drawings
Dendrochronology is the study of tree rings to investigate previous atmospheric conditions. Larger tree rings can show higher temperatures, higher CO2 levels, more rainfall, more sunlight, etc.
Disadvantages to this are that the trees must be chopped down in order to gain any information and also that individual factors cannot be measured with precision
Ice cores are used to measure the content of trapped air from up to 800,000 years ago within air pockets below ice covered landscapes. This can, for example, be used to measure the percentage of CO2 in the atmosphere during previous periods.
Disadvantages to this are that ice can be melted (ironically caused by climate change) and that ice cores only show data for the polar regions
Paintings and drawing from the past can be used to get an idea of past conditions
However this is a very inaccurate method due to exaggeration / understatement and quality of drawings.
The Greenhouse Effect
Greenhouse gasses - Carbon dioxide (81%), Methane (10%), Nitrous oxide, Flourinated gasses, water vapour, ozone
Recent
The Enhanced Greenhouse Effect
The greenhouse effect is a naturally occurring process in which greenhouse gases trap solar radiation inside the earth causing it to gradually warm
Shrinking glaciers and ice caps
Rising sea levels
Global temperature rise
Processes like deforestation and burning of fossil fuels contribute towards this
The greenhouse effect is being enhanced by humans due to an increase in greenhouse gas emissions
Increased frequency and severity of natural disasters
Worse conditions in warmer countries
Change and adaptions in industry
Income of poorer countries will decrease due to a negative effect on their market sectors
Farming in affected areas will become less profitable
Various health impacts to people in affected regions
Food and water scarcity in affected areas
Smaller land mass due to rising sea levels
Decrease in biodiversity due to change in conditions
Mass migration to more northern or southern countries from equatorial countries
Unpredictable weather and temperature patterns