What’s happening? Three months before world government representatives are to meet at COP26 in Glasgow to tie up the remaining elements of the Paris Agreement on climate change’s rulebook – which will be used as a basis to increase ambition on reducing emissions – the IPCC has released its latest seminal report on the science behind climate change, which paints a hard-hitting picture of the state of the world and the need to reduce emissions.
What is the IPCC saying? Using more sophisticated modelling techniques developed since its last global assessment in 2013, the IPCC has been able to state human activity is "unequivocally" causing climate change and extreme weather events. Governments worldwide have agreed to aim to limit the global rise in temperatures from pre-industrial levels to 1.5C, and the IPCC outlined in 2018 the efforts needed to do this – which will require a significant reduction in emissions from every area of the economy.
The world is currently 1.23C hotter than pre-industrial levels.
What else can we expect in the future? Well, without action, alongside a gradual rise in temperature, the extreme events we have been seeing more and more of in the news – heatwaves, flooding and wildfires for example – will occur more frequently. This will pose greater risks to human life, biodiversity and industries around the world.
A recent Nature study has indicated that heatwaves breaking today’s records by 5C will become two-to-seven times more likely over the next three decades, and three-to-21 times more likely from 2051-2080 without immediate cuts to emissions. Such extreme weather is increasingly being attributed to human-caused climate change in many regions of the world.
Separate recent analysis has indicated many key indicators of climate change are worsening and either getting close to or surpassing key tipping points – critical points at which subsystems of the Earth climate system are switched irreversibly into a different state.
For example, the disintegration of the West Antarctic ice sheet could reach a point of no return between 1.5C and 2C of global warming, at which point altered ice sheet dynamics will result in a total collapse regardless of changes in atmospheric temperature. This could lead to a sea-level rise of more than three metres.
Elsewhere, driven by climate change and deforestation, the Amazon rainforest might soon lose its ability to regulate its local climate, most importantly humidity and rainfall, and turn into a completely different biome: a savannah.
This is all pretty stark, so where do emissions need to go? Simply: in the other direction from where they’re going now.
In May 2021, despite a drop in annual global emissions in 2020 due to Covid-19-related lockdowns, monthly average CO2 levels hit 419 parts per million (ppm) for the first time, far beyond the 350 ppm threshold many view as “safe”. The International Energy Agency expects annual emissions to continue to rise and reach their highest ever level in 2023 as economies recover from Covid-19.
In order for the world to be aligned with limiting warming to 1.5C, emissions need to already be dropping by around 7% every year to 2030. That’s the reduction seen as a result of Covid lockdowns in 2020, every year.
The longer it takes for global emissions to peak and then start rapidly falling, the harder everyone will have to work to make it happen – highlighting the need for us all to address the issue and start to take action.
Impacts of climate change already affecting UK: report
The UK is already experiencing disruptive climate change and is seeing increased rainfall, solar irradiation and temperatures, according to the latest “State of the Climate” report. The last three decades have seen the UK become 0.9C warmer. (BBC)
Global food supplies hit by extreme weather
Extreme weather is damaging global crops and raising the prospect of further food inflation at a time when prices are already approaching their highest level in a decade and hunger is increasing. The UN’s Food Price Index has risen for 12 consecutive months through May 2021. (Bloomberg)
Gulf Stream currents at risk of shutdown due to climate change
The Atlantic meridional overturning circulation (AMOC), which controls the Gulf Stream, is at risk of shutting down due to climate change – which would have severe impacts worldwide. An AMOC shutdown would disrupt rainfall in South America, west Africa and India, lower temperatures in Europe and raise sea levels off the US east coast. (The Guardian)