Climate change: what is the science saying?
- Emily Latimer
- Jul 15, 2021
- 5 min read
Updated: Jul 21, 2021
The phrase 'climate change' is thrown around regularly, described by Sir David Attenborough as "a man-made disaster on a global scale" and "our greatest threat in thousands of years”. But what does it really mean and how bad is the situation?
What is climate change?
The Earth's average temperature is about 15C but has been much higher and lower in the past. There are natural fluctuations in the climate but temperatures are now rising faster than at many other times.
Climate change is the long-term shift in average weather patterns across the world. Since the mid-1800s, humans have contributed to the release of carbon dioxide and other greenhouse gases into the air.
Once in the atmosphere, greenhouse gases such as carbon dioxide form a 'blanket' around the planet. This blanket traps the heat from the sun and causes the earth to heat up. Evidence has shown that the high levels of greenhouse gases in the atmosphere are the leading cause of increasing global temperatures.
The world is already 1.1 degrees Celsius warmer than it was during pre-industrial years, and current emissions levels suggest that the planet will warm by an estimated four to five degrees Celsius by the end of the century, according to a new report by the United Nations’ World Meteorological Order (WMO).
What will this mean for the planet?
Such a rate of warming would cause catastrophic disruptions to the global environment including extreme sea-level rise, ocean acidification and a rise in extreme weather events.
Not only does this mean mass extinction for animals, but it could also be detrimental to humans, causing societal collapse and threats to our economy.
For example, according to the Met Office some of the impacts include:
Flooding of coastal regions – due to sea levels rising.
Food insecurity – due to high temperatures, extreme weather events, flooding and droughts damaging farmland.
Conflict and climate migrants – climate change can take existing problems, such as lack of food or shelter, and make them worse, causing conflicts over resources.
Damage to marine ecosystems – rising ocean temperatures, ocean acidification and ocean anoxia (lack of oxygen) are damaging to marine life such as fish and coral reefs.
The World Health Organisation estimates that between 2030 and 2050, climate change will be responsible for around 250,000 additional deaths a year.
Not just a 'thing of the future' -
Whilst climate change is often talked about as an event of the future, many of these impacts can already be seen in parts of the world today.
For example, over 1.3 billion people in the global south are relying on agricultural land that is slowly degrading.
Already, an average of 26 million people flee their homes every year due to climate-related disasters. On our current path, by 2050 it is estimated that there could be up to 200 million environmental migrants.
According to Morgan Stanley, between 2016-2018, climate-related disasters cost the world $650 billion.
For the first time, scientists have confirmed that the Amazon rainforest is now emitting more carbon dioxide than it is able to absorb.
The effects of climate change can be seen in recent events -
Oxfam estimates that the number of climate-related disasters has tripled in the last 30 years. It states: "Whilst we’ve always had hurricanes, droughts and wildfires, flooding and high winds, we are currently witnessing a scale of destruction and devastation that is new and terrifying." For example, some of these include:
Floods in western Europe- this month floodwaters have caused destruction in Germany, Belgium and the Netherlands where many have been left with wrecked homes, hundreds have been evacuated and officials continue to fret over the state of a major dam. More than 180 people have died.
Canada heatwave- the number of deaths recorded across British Columbia during the province's recent record-breaking heatwave reached 808. Those deaths were recorded from June 25 through July 1, as a brutal heat dome sent temperatures soaring to dangerous highs of 46.9 C in many communities.
South Asia floods- over the last year, deadly floods and landslides have forced 12 million people from their homes in India, Nepal and Bangladesh. Just two years ago, exceptionally heavy monsoon rains and intense flooding hit the same countries leaving a third of Bangladesh underwater.
Wildfires in the US- this month 80 large wildfires have been raging in 13 states across the U.S., burning more than one million acres of land, mostly in western states.
Australian wildfires- the start of 2020 found Australia in the midst of its worst-ever bushfire season. The fires burned through more than ten million hectares, killed at least 28 people, have taken the homes of thousands of families and left millions of people affected by a hazardous smoke haze.
How is climate change affecting the UK?
One way to contextualise climate change is to start by looking at the impacts closer to home. For example, according to Countryfile climate change has had the following effects in the UK:
Coastal erosion- sea levels around the UK have risen by 10cm since 1990, which means higher levels of coastal erosion. For example, in Devon, 2018’s Storm Emma washed away around 400m of the A379 between Slapton and Strete Gate.
Flooding- total UK rainfall has increased by 17% since the 1960s. This means an increase in flooding, particularly in areas where rainfall is already high, such as Cumbria, Lancashire and the west coast of Scotland. In November 2016, the UK Government allocated £15 million to natural flood management projects in England.
Shortages of food and water- within the UK it is expected that there will be increased pressure and shortages of water and food. The Committee on Climate Change has called for changes in land practice to mitigate the impacts of climate change, including a reduction in livestock numbers, increased tree planting, improved forest management and restoration of peatlands.
Air Pollution- air pollution alone is already responsible for an estimated 40,000 excess deaths a year in the UK, a figure that is expected to increase.
So, what is being done?
National Geographic suggests: "Humans have the solutions to address climate change. The question is: Do we have the will?"
Countries around the world have acknowledged the need to act on climate change in the Paris Agreement 2015, making pledges to reduce greenhouse gas pollution. The Intergovernmental Panel on Climate Change (IPCC), which gathers scientific consensus on the issue, has set a goal of keeping warming under two degrees Celsius and pursuing an even lower warming cap of 1.5 degrees Celsius.
However, major countries are already falling behind on their pledges; according to a UN report issued at the end of 2018 emission levels in 2030 need to be around 25% to 55% lower than they were in 2017. Previous research suggests that even if countries do meet their pledges to reduce emissions, those commitments won't be enough to stave off severe warming.
What solutions are needed?
Required changes span technologies, behaviours and policies that encourage less waste and smarter use of our resources.
According to the Union of Concerned Scientists, we need to:
Cut emissions- we need a massive transformation in how we produce and consume electricity such as increases in wind and solar power, biofuels from organic waste, setting a price on carbon, protecting forests, a climate-friendly agricultural system and a better transportation system.
Remove carbon dioxide- as well as reducing our emissions, we need to actively remove carbon dioxide from the atmosphere or offset its effects. The easiest way to do this is by planting new forests (afforestation) or restoring old ones (reforestation). Other enhanced land management practices can help, as can new technologies that remove CO2 from the air.
Prepare and adapt- cutting carbon is the only long-term solution for avoiding climate impacts. In the short term, we need to adapt and invest. That means everything from discouraging development in high-risk areas, to planning for water scarcity, to building more resilient cities and communities.
There is no quick fix to climate change and according to an IPCC report in 2018: "Limiting global warming to 1.5ºC will require rapid, far-reaching and unprecedented changes in all aspects of society."
As Sir David Attenborough states: “It’s clear that we’ll have to change the way that we live and use our resources. We’re at a crossroads where we can choose to cooperate or carry on regardless."
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