Climate Change: A Very Short Introduction

by Mark Maslin

However, this energy source is not an option for aeroplanes.

Many power stations around the world have been converted so that they can burn wood pellets instead of coal or natural gas to create steam to turn the turbines to make electricity. Critics have argued that wood pellets are not sustainable and do not have as low a carbon footprint as claimed.

One study suggests that wind in principle could globally generate over 125,000 terawatt-hours, which is five times the current global electricity requirement.

experts in the field suggest that wave power technology is 20 years behind solar panel technology.

There is also debate about how much GHG emissions hydroelectric plants save, because even though the production of electricity does not cause any carbon emissions, the rotting vegetation in the area flooded behind the dam does give off significant amounts of CH4

There is, however, another way the warmth of the Earth can be used. All new buildings could have a borehole below them with ground-sourced heat pumps. Cold water can then be pumped down into these boreholes, with the ground warming the water up, cutting the cost of providing hot water to buildings. This method could be used almost everywhere in the world.

Power production costs that include CCS would rise by at least 15% and could be as high as 100%.

In many developed countries the carbon emissions from energy production, business, and residential sectors are all going down despite annual growth in the economy; but transport emissions, mainly from cars and aviation, are still increasing.

not only can we build much more efficient aeroplanes today, but there are alternative fuels that could be used. Biofuels could be developed as an additive or even as a replacement for traditional air fuel kerosene.

One of the most important ways to remove CO2 from the atmosphere is through reforestation and rewilding.

Massive reforestation isn’t a pipe dream; it can have real benefits for people. In the late 1990s, environmental deterioration in western China became critical, with vast areas resembling the Dust Bowl of the American Midwest in the 1930s. Six bold programmes were introduced, targeting over 100m hectares of land for reforestation. Grain for Green is the largest and best known of these. These radical tree-planting programmes had an amazing effect as the trees stabilized the soils, greatly reducing soil erosion and the impacts of flooding.

In 2019 researchers claimed in the journal Science that covering 900m hectares of land—roughly the size of the continental US—with 1 trillion trees could store up to 205 billion tonnes of carbon, about two-thirds of the carbon that humans have already put into the atmosphere. The ‘1 trillion trees’ mantra has caught the popular imagination and even President Trump declared at the Davos meeting that this was a good idea. The only problem is that the research that produced this high carbon number was fundamentally flawed and in fact the IPCC and other studies suggest that new forests could store on average an extra 57 billion tonnes of carbon by the end of the century.

Already 63 countries have joined the Bonn Challenge and pledged to restore 350m hectares of degraded land to forest worldwide.

Reforestation and afforestation are fundamentally limited by the land area available, as trees can only hold a finite amount of carbon. We must also remember that reforestation is not always the best option, and this is why the term ‘rewilding’ is used in conjunction with reforestation. For example, draining wetlands or peatlands to plant forests is counter-productive, as the carbon storage will be lower and losses of biodiversity will be considerable.

One of the criticisms of the Bonn Challenge is that about half the pledges involve large-scale commercial forest plantations. Plantations only lock up carbon while the trees are growing, and much of this is returned when they are harvested. In any case, monoculture is bad for biodiversity.

Citizens all around the world have been shown that there can be a different relationship between government, industry, and civil society—a relationship where health and wellbeing are put before economic gain for a country or small minority of individuals.

Though individual actions will only make a small contribution to carbon reduction, they are extremely important as they send a strong message to both government and corporations that citizens want and support major changes.

If the UN Environment Agency were to be upgraded to the UN World Environment Organization (WEO), and given a budget at least the size of that of the WHO,

Berners-Lee, M. There Is No Planet B: A Handbook for the Make or Break Years (Cambridge University Press,

Wallace-Wells, D. The Uninhabitable Earth: A Story of the Future (Penguin, 2019).