What causes climate change?

What causes climate change?

Burning fossil fuels for energy, transport and industry releases greenhouse gases, which cause global warming. Things like farming, cutting down forests and overfishing are making it worse. There is no doubt that human activities are causing climate change, which means we are also able to stop it.


The main cause of climate change is burning fossil fuels – such as coal, oil and gas – to produce energy and power transport.

Along with other human activities, like cutting down forests and farming, this releases heat-trapping pollution called greenhouse gases into the atmosphere, warming the planet and destabilizing the climate.

The world is now warming faster than at any point in human history. The effects are extreme weather like heavy rain or droughts, long-term shifts in weather patterns, melting ice and rising sea levels. Climate change is already having huge impacts on people and the environment worldwide.

Human activities that release greenhouse gases need to be urgently curbed as much as possible to ensure a stable climate and safe world for everyone.
Where do greenhouse gases come from?

There are a number of human activities that we know to be damaging to the climate. These mostly involve generating energy, because huge amounts of energy are needed to keep our modern world running.Generating energy – a lot of power generation for electricity and the vast majority of home heating are still done by burning fossil fuels, such as gas. Historically, the MENA region’s contribution to greenhouse gas emissions has been minimal, but the region now accounts for about 30% of global oil production and 18% of natural gas production. With the energy sector contributing more than 70% of the world’s CO2 emissions, the region’s fossil fuel production in the past decade has made it one of the regions with the highest per capita CO2 emissions, according to a report by the Natural Resource Governance Institute (NRGI).
Transport – cars, buses, trains, trucks, ships and planes, (unless electric and charged with renewable energy), all produce emissions by burning fossil fuels. International aviation and shipping will continue to be a significant contributor to climate change until demand reduces or alternatives to fossil fuels become available.
Food production – livestock reared for meat and dairy products emit methane, and agricultural soils emit gases like nitrous oxide, which is made from nitrogen in the soil through the use of fertiliser. As food production increases (with more fertilisers, more livestock, and the need for more crops to feed livestock), emissions will also increase.
Deforestation – because trees store carbon as they grow, cutting or burning down trees releases that carbon into the atmosphere. Farmers may cut down trees or clear land using fire to produce soya for animal feed, such as in the Amazon. In other parts of the world, natural forests are cleared for timber, mining or palm oil.
Powering industry – since the Industrial Revolution began in the 18th century in the UK, humans have burned fuel such as coal, oil and gas in order to drive large-scale industries. Industrial emissions come from producing things like cement, iron, steel, electronics, plastics and clothing. All countries are now largely dependent on fossil fuels to build and sustain their economies.
Plastics and waste – plastics are made from fossil fuels, releasing emissions through their production. Globally, about 40% of plastics are used as packaging. Because so little is recycled (and it would be hard to recycle that much plastic anyway), dealing with waste releases emissions when incinerated (burned) or put into landfill – making it a bigger climate problem than it initially seem
What are greenhouse gases and how do they cause climate change?
Greenhouse gases include carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), which trap heat in the Earth’s atmosphere, increasing the average temperature worldwide.

These gases are naturally present in the atmosphere but human activities have massively increased them, trapping heat that then causes climate change.
Carbon dioxide

From burning fossil fuels, deforestation
Methane

From natural gas, permafrost melt, flooding
Nitrous oxide

From fertiliser used in farming.
The tipping points that could make climate change irreversible

The Intergovernmental Panel on Climate Change has warned that there could be catastrophic consequences if humanity allows global temperatures to warm by over 2ºC (the ultimate limit set by the Paris Agreement).

While scientists now agree that atmospheric warming can be stopped once emissions are brought down or stopped, tipping points complicate things.

A climate tipping point is when small changes combine to become significant enough to cause larger, more critical changes to our climate and our planet, which are likely to be irreversible.

Here are the major tipping points scientists are warning governments about:Polar ice sheets collapsing in Greenland and Antarctica – while it is melting slowly, the eventual collapse of the Greenland ice sheet would be irreversible, and sea levels around the world would rise by up to seven metres, leaving cities like Miami, Alexandria and Mumbai underwater. Scientists are also now concerned about the potential collapse of the West Antarctic ice sheet, which would also have extreme effects on the coastlines around the world.
Arctic permafrost melt – as the atmosphere heats up, the Arctic permafrost is melting, releasing greenhouse gases stored underneath it, such as methane.
Changing oceans are shifting weather patterns – fresh water from the Greenland ice sheet is melting into the Atlantic ocean, causing the Gulf Stream to slow, leading to extreme cold snaps and colder winters in the US and Europe. The oceans are also absorbing heat generated by greenhouse gas emissions, affecting wildlife and livelihoods around the world, including strengthening El Niño and La Niña weather patterns around the Pacific Ocean.
Amazon rainforest collapse – the Amazon rainforest is being destroyed and burned to make way for farming, and now produces more than a billion tonnes of carbon dioxide a year, which is now more than it absorbs. If it dries up, billions more tonnes of carbon dioxide would be emitted into the atmosphere, disrupting rainfall across South America and altering climate patterns in other parts of the world.