What is climate change?

Since the industrial revolution began, humans have been burning vast amounts of fossil fuels – coal, oil, gas – to move around, heat buildings and make stuff.  This, along with deforestation and some agricultural practices, has led to increased amounts of carbon dioxide and other greenhouse gases in the atmosphere. These have the effect of trapping more heat from the sun and have raised the average temperature of planet earth by around 1°C so far, mostly in the last 40 years and with the 20 warmest years ever recorded happening in the last 22 years.

A 1°C average rise has caused noticeable effects: sea levels have risen around 20 cm, extreme weather events (floods, heatwaves, hurricanes) around the globe are more frequent and severe than in the past.  If we carry on as we are, CO2 levels will continue to rise and by the end of the century scientists predict a temperature rise of between 3°C and 6°C. The effects of this are hard to imagine: Sea levels would have risen by several meters causing complete abandonment of some coastal cities and entire island nations; food shortages would result from large scale frequent crop failures;  droughts and water-shortages will be more common and devastating; heat and extreme weather would make some areas of earth uninhabitable displacing hundreds of millions of people.

We need to do something, and a comprehensive report from the UN tells us what and when we need to do it.  (Short answer: a lot, soon.) Thousands of expert climate scientists from across the world have modeled how much carbon dioxide and warming our climate can cope with.  They show that there is a very big difference between the warming carrying on to produce an average temperature rise of 2°C versus 1.5°C (remember we have already had about 1°C  already). The effects of warming to 2°C vs 1.5°C are directly more impactful (eg all coral is predicted to bleach at 2°C but some survives at 1.5°C) and the warmer we get the harder it is to stop further warming.  So-called tipping points, essentially positive-feedback to the warming process, come into play: Melting of ice from Greenland and Antarctica mean the reflective white ice is replaced by more heat-absorbing rock that heats faster; methane (around 30 times more potent a greenhouse gas than CO2) trapped in frozen ice and tundra is released.  Once we go past the 1.5°C earth can just about cope with, it is harder to stop the warming process.

To keep warming to 1.5°C,  rather than the vastly more damaging 2°C  or beyond, we need to reduce global greenhouse gas emissions by around 45% by 2030 (from 2010 levels) and to net-zero by 2050, at the latest. When the reductions are made are as important as the scale of the reductions. If we reduce our CO2 emissions by 20% by 2030 we are heading for a 2°C rise.  With current emissions and warming rates we could see a 2°C rise as soon at 2030. Depressingly, the current global commitments to reducing greenhouse gas emissions don’t put us on the path to keeping warming under 2°C. We need to do more.

 

FAQs

What can I do to help?

Have a look at our advice section for the big actions to reduce your impact.  

 

What is the Climate Emergency I saw in the news?

Climate emergencies have been declared by many governments at various levels and in several nations.  Locally climate emergencies have been declared in Wells, Mendip, Somerset, Bristol, Bath and nationally by the UK parliament.  Broadly, these acts are to acknowledge that we face an imminent danger and need to concentrate on our efforts and responses. Often a commitment to become carbon-neutral by a specific date is made, which is good because it involves considering how all actions the governing body is responsible for effect this balance.  Of course declaring a climate emergency is not enough: we need to undertake significant actions and Sustainable Wells is keen to support these however we can and you can learn more here.  

 

Ok, I’m convinced – I’m recycling, switched to green power and planted a tree – am I carbon neutral?  

Great job doing all those things, they are all good, but have a look at your total carbon footprint.  Emissions from say driving, flying or shopping can completely dwarf other reductions. It’s important to look at the total picture and aim to act on the largest parts.  It’s really hard to be carbon neutral for now but the closer you can get, and the sooner, the better!

 

Is a few degrees of warming really that significant? Summer and winter vary by much more than that every year.  

Yes – remember it is average temperature rise across the entire planet that is often discussed.  The warming is far from even – for example the arctic region has had proportionality far larger temperature rises – and a lot of the damage from climate change is from the more frequent and severe extreme weather events.   

 

Aren’t scientists working out how to just remove the CO2 from the air?  

Yes, but we don’t really know if any of the methods are going to work.  Trees definitely work (you’ve probably seen them around) but when you look at the numbers it’s quite surprising how many you need to soak up a decent amount of carbon.  Our best guess at present is that sequestration won’t ever balance more than a small fraction of our current emissions. We need to drastically reduce our emissions and then the small amounts left that are really hard to eliminate could probably be negated by some form of capture.

 

What about China, don’t they emit vast amounts and anything we do is trivial?  

China makes an incredible amount of stuff that we buy.  If you take the emissions associated with making things and assign them to the countries in which the consumers live, China’s emissions look a lot lower and on a per capita basis emissions are much lower than ours.  Plus China are world leaders in renewable energy and are making huge strides towards massive amounts of solar power generation. The problem is caused by everybody, therefore all nations need to get their house in order.

 

Won’t the economy collapse if we do things to reduce our co2 emissions?  

It might make more sense to ask “won’t the economy collapse if we don’t reduce our co2 emissions?”  If we keep warming the planet, sea levels will continue to rise and extreme weather will become more frequent and damaging.  The economic impact of floods, fires, drought, crop loses and even destruction of entire cities are vast. Decarbonizing the economy doesn’t obviously involve economic reduction – there will still be energy, homes, transportation . . . just low carbon forms.  

 

Where can I find out more about climate change?

There is a vast array of information available, here are some of the best . . .

https://www.bbc.co.uk/news/science-environment-24021772

https://en.wikipedia.org/wiki/Global_warming

https://www.carbonbrief.org/

https://climate.nasa.gov/evidence/

https://www.metoffice.gov.uk/weather/learn-about/climate-and-climate-change/

https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions