SUpporting Information
There is nothing new about climate change. For hundreds of millions of years the Earth’s temperature has been influenced by continental shifts, which have triggered volcanic eruptions among other things. Sometimes these shifts released large volumes of CO2 which heated up the Earth. They also caused young rocks to rise to the surface, which chemically bound CO2. As a result, CO2 was dispelled from the atmosphere in the longer term. Sea levels are rising and oceans are becoming warmer. Longer, more intense droughts threaten crops, wildlife and freshwater supplies. From polar bears in the Arctic to marine turtles off the coast of Africa, our planet’s diversity of life is at risk from the changing climate.
Humans have been influencing the climate since the start of the Industrial Revolution. Since then, the average world temperature has risen by approximately 0.8 degrees Celsius. In North-West Europe (including the Netherlands) the average temperature has risen by 1.5 degrees. The sea level has risen by around twenty centimetres and most of the glaciers have shrunk dramatically.
Up to 1950 the influence of nature was more important than human influence. After that, the pattern in the average world temperature can only be explained by factoring in the human influence.
Even so, a slight decline in temperature did appear from the mid-1940s to the mid-1970s. It was linked to a dramatic increase in cooling aerosols from the post-war industrialisation in the western world. It was also caused by a mild decline in solar activity and some major volcanic eruptions in the second half of this period. According to the latest IPCC report, it is more than likely (more than 90 per cent probability) that most of the global warming in recent decades is attributable to the observed increase in greenhouse gases.
Humans have been influencing the climate since the start of the Industrial Revolution. Since then, the average world temperature has risen by approximately 0.8 degrees Celsius. In North-West Europe (including the Netherlands) the average temperature has risen by 1.5 degrees. The sea level has risen by around twenty centimetres and most of the glaciers have shrunk dramatically.
Up to 1950 the influence of nature was more important than human influence. After that, the pattern in the average world temperature can only be explained by factoring in the human influence.
Even so, a slight decline in temperature did appear from the mid-1940s to the mid-1970s. It was linked to a dramatic increase in cooling aerosols from the post-war industrialisation in the western world. It was also caused by a mild decline in solar activity and some major volcanic eruptions in the second half of this period. According to the latest IPCC report, it is more than likely (more than 90 per cent probability) that most of the global warming in recent decades is attributable to the observed increase in greenhouse gases.
The most well-known and the most important greenhouse gas is CO2. The concentration of CO2 in the atmosphere is subject to variation even without human intervention. The carbon cycle causes an exchange of CO2 between the biosphere and the oceans on the one hand and the atmosphere on the other.
Vast amounts of CO2 are also released by the burning of fossil fuels. There is incontrovertible evidence that the CO2 concentration in the air has never been so high in 800,000 years (probably even 60 million years) as it is now. The trend suggests that CO2 emissions will continue to rise globally, although the economic crisis did prevent a rise in 2009. The Netherlands (per head of population) is high on the list of CO2 emitters in the world.
Besides CO2 , methane (CH4), nitrous oxide (N2O), fluorinated gases, ozone (O3) and water vapour are important greenhouse gases. Water vapour plays a unique role as it strengthens the heat-trapping effect caused by other greenhouse gas emissions. This is because a warmer atmosphere retains more water. The amount of water vapour cannot be artificially increased or decreased.
Vast amounts of CO2 are also released by the burning of fossil fuels. There is incontrovertible evidence that the CO2 concentration in the air has never been so high in 800,000 years (probably even 60 million years) as it is now. The trend suggests that CO2 emissions will continue to rise globally, although the economic crisis did prevent a rise in 2009. The Netherlands (per head of population) is high on the list of CO2 emitters in the world.
Besides CO2 , methane (CH4), nitrous oxide (N2O), fluorinated gases, ozone (O3) and water vapour are important greenhouse gases. Water vapour plays a unique role as it strengthens the heat-trapping effect caused by other greenhouse gas emissions. This is because a warmer atmosphere retains more water. The amount of water vapour cannot be artificially increased or decreased.
Greenhouse gasesSome gases in the Earth's atmosphere act a bit like the glass in a greenhouse, trapping the sun's heat and stopping it from leaking back into space.
Many of these gases occur naturally, but human activity is increasing the concentrations of some of them in the atmosphere, in particular:
Other greenhouse gases are emitted in smaller quantities, but they trap heat far more effectively than CO2, and in some cases are thousands of times stronger. Methane is responsible for 17% of man-made global warming, nitrous oxide for 6%
Many of these gases occur naturally, but human activity is increasing the concentrations of some of them in the atmosphere, in particular:
- carbon dioxide (CO2)
- methane
- nitrous oxide
- fluorinated gases
Other greenhouse gases are emitted in smaller quantities, but they trap heat far more effectively than CO2, and in some cases are thousands of times stronger. Methane is responsible for 17% of man-made global warming, nitrous oxide for 6%
Causes for rising emissions
- Burning coal, oil and gas produces carbon dioxide and nitrous oxide.
- Cutting down forests (deforestation). Trees help to regulate the climate by absorbing CO2 from the atmosphere. So when they are cut down, that beneficial effect is lost and the carbon stored in the trees is released into the atmosphere, adding to the greenhouse effect.
- Increasing livestock farming. Cows and sheep produce large amounts of methane when they digest their food.
- Fertilisers containing nitrogen produce nitrous oxide emissions.
- Fluorinated gases produce a very strong warming effect, up to 23 000 times greater than CO2. Thankfully these are released in smaller quantities and are being phased down by EU regulation.
Sources Used:
- Wageningen university report
- European Commission
- WWF