Yes, there’s still time to limit climate warming to 1.5C – major report
A highly anticipated scientific report on the world's efforts to curb climate change has been released . The latest global climate report went right down to the wire, with negotiators working overtime to reach an agreement, delaying the release from 10pm yesterday to 3am New Zealand-time. Heres the eight things you need to know about this mornings critical report from the worlds climate scientists: There is still time left to limit warming to 1.5 degrees Celsius. The 1.5C temperature goal appears in the Paris Agreement (the accord to limit global heating agreed to by 197 governments). Beyond 1.5C, the science indicates the effects of global heating will get disproportionately worse. Currently, the world is 1.1C warmer than pre-industrial times. At 1.5C, the oceans will rise faster, extreme weather such as droughts and heatwaves will become more frequent, and crops, plants and animals will shift to different locations (with the pressure pushing some to extinction). But staying inside 1.5C could halve the amount of land lost to the ocean, reduce the number of people exposed to natural disasters and allow some species to hold on. Humanity has already spent more than four-fifths of the carbon budget we could emit and still have a 50:50 chance of staying inside 1.5C. But we still have an opportunity: if emissions peak by 2025 at the latest and fall quickly and steeply in the 2030s, 40s and 50s, the globe could stay inside the much safer zone. For that to happen, emissions need to fall about by 43 per cent from their pre-pandemic levels by 2030 and 84 per cent by 2050. Almost all sectors would need to make deep reductions, and move immediately. READ MORE: * From pseudo-volcanoes to carbon-sucking rocks. Can technology fix the climate? * The complex ways climate change is impacting our mental health * Scientists and most governments say fossil fuels must plummet by 2050. National's new adviser disagrees The world particularly the wealthiest and developed nations has failed to take meaningful action on emissions. Since the release of the last Intergovernmental Panel on Climate Change (IPCC) report in 2014, there has been little progress in limiting global emissions. From 2010-2019, average yearly emissions were higher than ever before (producing 17 per cent of all cumulative carbon emissions since 1850). The only positive: this growth appears to be slowing. By allowing emissions to rise, most countries have essentially walked back from the starting line, making their task a lot harder. Government commitments and ramped-up pledges out to 2030 are a positive step since the last report, the authors said. But even if these are met, the world is likely to top 1.5C this century and governments policies to date are not on track to achieve their pledges (in fact, global emissions are expected to rise). The report also stressed the links between wealth, location and emissions. Those with the lowest emissions often suffer from energy poverty and poor standards of living. Globally, the carbon footprint of the most-polluting 10 per cent of households is more than double the size of the least-polluting 50 per cent, it said. But its possible to change: at least 18 countries have been driving emissions down consistently for longer than ten years. (New Zealand is not one of them). After dithering, the world will need to invest heavily in low-carbon electricity, transport, buildings and cities and leave fossil fuels in the ground. If all existing and planned fossil fuel infrastructure is allowed to live out its natural lifespan, the unchecked emissions from that alone will push the planet over its carbon budget for 1.5C, the report concluded. By 2050, almost all electricity would need to be from zero or low-carbon sources and more activities would need to run on electricity. Although the costs of climate inaction are higher than the cost of limiting warming to 2C, the world will need to make significant investments to transition to a low-carbon economy but this finance isnt flowing as fast as it needs to. Carbon pollution is the major driver of climate change. This greenhouse gas comes predominantly from the burning of fossil fuels. But carbon dioxide is also released when forests are cleared for agricultural, industrial or residential use. In New Zealand, native forest was being lost, though the One Billion Trees programme may have turned that around. But the world is losing more forest than is being planted. Cutting natural gas and agricultural emissions will lower peak heat and help avoid dangerous temperatures. Methane is 34 times more potent than carbon dioxide over the course of a century, according to the scientists. But methane only lives a short time for around 12 years before it breaks down into carbon dioxide. Policies to drastically reduce methane outputs would have a noticeable effect on temperatures much sooner than those targeting carbon dioxide. Because the world is quickly running out of time to limit warming to key temperature goals, targeting methane will need to be part of the package, the report highlights. For example, when the authors looked at a range of emissions paths that would give the planet a decent chance to stay inside 1.5C, they found carbon dioxide needed to drop by about 48 per cent compared to pre-Covid levels by 2030 while methane needed to fall by about 34 per cent. By 2050, methane would have fallen 45 per cent from 2019, which is the maximum amount the modellers think is feasible, while carbon dioxide would approach zero. There are two key types of methane: fossil methane (which we know as natural gas) and biological methane (whats produced by livestock and landfills). Fossil gas entering the atmosphere is particularly problematic, because it not only powerfully heats the climate, but it then adds extra carbon dioxide to the air as it breaks down. The report concluded emerging tech to reduce livestock methane and nitrous oxide was promising but challenges remained. Some good news: renewable energy and electric-powered tech is ready to replace fossil fuels . Green energy is earning a place in the spotlight, as renewable generation has never been cheaper. Solar power and EVs are growing in leaps and bounds. But we need more: plenty of EVs, but also walking, public transport and cycling plus snug, low-carbon buildings. At the same time, the world could reduce emissions in 2050 by up to 70 per cent simply by avoiding waste, the report said. The efficiencies of LED lights, heat pumps, electric cars, car sharing, remote working right up to compact, well-designed cities all add up. These gains would need to drive fossil fuel use down (not sideways). Your climate efforts matter, a little. Can people help to prevent climate catastrophe by actions such as changing to a diet rich in plant-based foods and minimising food waste? The report authors concluded these efforts can play a minor, but still significant role: preventing 2 billion tonnes of emissions each year. In addition, public engagement influences political support for carbon-cutting pledges and policies, the authors said. Carbon must be sucked from the air and stored permanently. Humanity is reaching and may have passed the point where it could limit warming to 1.5C by cutting greenhouse pollution alone. This means were likely to, at the very least, temporarily overshoot our temperature target goal. To get temperatures back down again, young and future generations will need to pay to suck up vast quantities of carbon dioxide. Currently, the most feasible and accepted way to sequester carbon is by planting trees and well need them to suck up between 5 and 6 billion tonnes each year (thats 8 per cent of global greenhouse pollution emitted in 2019). But the report warned the world cannot plant its way out of climate change. IPCC scientists believe artificial carbon removal is increasingly necessary: machines sucking carbon directly from the air to be pumped underground. Currently, there are a few pilot projects currently operating or in development, but these are sucking up just a drop in the ocean, compared to global emissions. Another carbon-negative idea is to use trees to collect the carbon, instead of machines. The wood is burned to create energy, and then the carbon dioxide is separated out and sent below ground. For an even shot at 1.5C, the models found these technologies would sequester between 30 billion and one trillion tonnes of carbon dioxide, the report said. The authors also noted that some carbon removal will balance out the remaining emissions of the day but many machines would be running to mop up excess pollution were creating today. Unrealistic expectations around artificial sequestration shouldnt be used as an excuse to delay action. The report was produced by the third working group of the IPCC, drawing on more than 18,000 pieces of published research and the work of 278 authors. New Zealand scientist Andy Reisinger is vice chair of this working group, making him the most senior New Zealander involved in the process. This is the sixth time the whole process has been conducted since the 1990s, with the fifth working group producing a set of four reports between September 2013 and October 2014. For the sixth round, the first instalment detailing the multiple lines of evidence that the climate is heating and that human activities are to blame was released in August. The second report, on the worsening floods, fires, droughts, heat waves and other disasters that would come with a hotter planet , was published in March. The main body of the report is written by scientists from around the world, working cooperatively. However theres also a summary version that is mainly used by governments in the intervening years and this has to be agreed by government representatives from countries signed up to the UN climate treaty, as well as the authors. They scrutinise every line of this summary until theres a consensus. The publication of this third reports summary went down to the wire, with the official press conference and release of the report and a shorter summary delayed by six hours while senior authors and government delegates debated. Altogether, the first three reports will be compiled into a fourth, synthesis report, which is due to be published in September. Stuff will continue to cover the release of the IPCCs third report in the coming days.