According to a report by the United Nations Environment Program (UNEP), if countries keep their latest promises to reduce emissions by 2030, the planet will warm by at least 2.7 degrees Celsius this century. This exceeds the critical internationally agreed temperature of 1.5 °C.
Launched just days before the start of the International Summit on Climate Change in Glasgow, UNEP’s Emissions Gap Report tackles the gap between projected greenhouse emissions for 2030 and where they should be to avoid the worst effects of climate change. Is.
Australia has officially committed to a zero net emissions target by 2050. The government has not changed its 2030 target of reducing emissions by between 26% and 28% from 2005 levels, but has declared the country is poised to win. up to 35%.
The UNEP report was prepared before Australia’s new target for 2050 was announced, but even with this new promise, the global commitment will no doubt be what is still needed.
The report concluded that the global target of net zero emissions by mid-century could cut global warming by 0.5 °C. Although this is a big improvement, the temperature will increase by 2.2 °C in this century. If we do not close the global emissions gap, what will Australia and the rest of the world be forced to suffer?
less promises than necessary
As of 30 August (the date UNEP was revised), 120 countries had made new or updated pledges and declarations to reduce emissions.
For example, the US has set an ambitious new target of reducing emissions by 20-50% below 2005 levels by 2030. Similarly, the EU will cut carbon emissions by at least 55% by 2030 compared to 1990 levels.
But the UNEP report shows that all these promises are not up to the mark. It concludes that we will have to take in an additional 28 million tonnes of carbon dioxide equivalent to annual emissions by 2030, which has already been promised.
UNEP also found that while effectively meeting the net targets of zero by mid-century could reduce the projected rise in temperature, current plans are unclear, with many deferred action until after 2030, when it is too late. Will go These net zero targets, including those in Australia, are also based on technologies that do not yet exist on a large scale, such as carbon capture and storage.
UNEP’s findings echo a briefing note from Australian climate scientists who say that even if global net emissions hit zero by mid-century, there is a high probability that temperatures will exceed 2 °C in this period if We neglect to increase the action of the short term.
When the UNEP report was created, 49 countries and the European Union promised a net target of zero, equivalent to a third of the population and half of global emissions. Eleven of these targets are enshrined in law, representing 12% of global emissions.
Did COVID-19 make a difference? Although carbon emissions fell from 5% to 6% in 2020, this was due to worldwide blockades and other restrictions rather than permanent changes to the way society works.
The report said that as restrictions are eased, emissions are expected to rise again dramatically this year, slightly lower than in 2019. To avoid the worst effects of climate change, a sustainable annual reduction in carbon emissions is needed.
what does this mean?
So far, the world has warmed by about 1.2 °C above pre-industrial levels, and we are already experiencing significant impacts from climate change and worsening of extreme weather events.
A heat wave hit western North America in late June this year with record temperatures and extreme deaths. This event would have been nearly impossible without man-made greenhouse gas emissions warming the planet.
Similarly, the extreme rainfall caused by recent floods in central Europe that devastated cities in July was likely exacerbated by global warming.
In Australia, we have seen our share of extreme events in recent years that have been exacerbated by climate change, including record-breaking summers and the devastating wildfires of 2019 and 2020.
Complying with the Paris Agreement and keeping global warming below 2 °C or 1.5 °C will still lead to continued sea level rise and worsening heat waves over land and oceans.
If we don’t abide by the Paris Agreement and end up warming the world by about 3 degrees Celsius by 2100, the effects of climate change will be significantly worse.
Warm water coral reefs, including the Great Barrier Reef, are already stressed by repeated bleaching events and may already be at the edge of precipitates. Most coral reefs probably won’t survive 1.5°C, which is much less than 3°C. However, limiting warming to 1.5 °C instead of 2 °C makes a huge difference for many other ecosystems.
Historically hot summers such as the fiery summers of 2012 and 2013 and the black summers of 2019 and 2020 will be 2 °C to 3 °C warmer than most Australian summers in the world. During the heat wave, temperatures in parts of Sydney and Melbourne are likely to hover around 50 degrees Celsius.
And with global warming of 2 °C to 3 °C, most of the continent will have more short bursts of extreme rain that cause flash floods. Meanwhile, the drought is expected to worsen, especially in the southwest and southeast.
While Australia will be greatly affected by climate change if the world does not abide by the Paris Agreement, the prospect is far worse and more devastating for less wealthy countries. Intense heat waves, more extreme rain and drought will make life more difficult for many people, as developing countries lack the resources to adapt.
A big job for COP26
It is imperative to avoid the effects of climate change that come with an average temperature rise of 2°C to 3°C.
To face any chance of meeting the goals of the Paris Agreement, all countries will need to significantly increase their ambition and promise a much greater reduction in carbon emissions from Glasgow.
Wealthy, high-emissions countries must move forward with strong promises and agreeing on terms for funding climate mitigation and adaptation in developing countries.
Time is fast running out to avoid more dangerous climate change, and the world cannot afford to miss an opportunity at COP26.
* Andrew King is a Research Fellow at the University of Melbourne, and Malte Meinshawson is an Associate Professor at the University of Melbourne. The text was originally published in English Conversation,