LONDON, April 4 (Reuters) - The U.N. climate science panel's report Monday, the last of the current scientific assessment cycle, finds that emissions are still rising with the world at risk for runaway climate change.
Here are some of the report's main conclusions:
EMISSIONS ESCALATING
The world has not yet managed to reduce its emissions output, hitting about 59 gigatonnes in 2019 when changes in land use are taken into account. That's a 12% jump from global 2010 emissions of 52.5 gigatonnes, or an average increase of 1.3% each year during the last decade.
By comparison, global emissions in the previous decade climbed by about 2.1% each year, or nearly twice as fast. While total emissions are still rising, the rate of increase has slowed.
Increases came from all industries, including energy, transportation and agriculture. In the power sector, the expanded use of renewable energy as well as improvements in energy efficiency did not go far enough to counteract emissions from growing industrial activity and population growth worldwide, the report says.
ON TRACK FOR A HOTHOUSE PLANET
Only immediate, ambitious climate action will keep global temperatures from rising 1.5 degrees Celsius beyond the pre-industrial average, the report says. Beyond that threshold, the world would be courting extreme climate change with severe impacts on people, wildlife and ecosystems, scientists say.
Current emissions trajectories, if unchanged, put the planet on a path to warm by about 3.2 degrees C. If current national climate commitments are enacted, they still would fail to limit warming to 1.5 degrees C, instead putting the world on track for at least 2.2 degrees C if not more, the report says.
Holding warming to within 1.5 degrees C requires cutting emissions of all greenhouse gases roughly in half by the 2030s, and achieving net-zero carbon dioxide emissions in the 2050s.
That would require using about 95% less coal, 60% less oil, and 45% less gas by 2050. Electricity grids run on renewable energy sources would need to meet much more of the world's energy needs. Cities would need to improve energy efficiency through better building strategies to reduce urban emissions.
LIMITED ECONOMIC GROWTH
Containing warming to 2 degrees C would require actions that limit global economic growth by 1.3% to 2.7% by 2050, the report says. However, that loss would likely be outweighed by the overall economic benefit of limiting warming, it says.
Governments also would need to enact policies toward changing people's lifestyles and behaviors, such as encouraging work from home to reduce travel, reducing car use in favor of cycling and walking, or promoting plant-based diets over meat consumption.
These would cost some sectors but boost others while also preventing losses in areas such as public health.
Such "demand-side mitigation" efforts could reduce global greenhouse gas emissions in some sectors by up to 70% by 2050, the report says.
SIGNS OF PROGRESS
A few bright spots are highlighted in the report, including the increasing affordability of climate-friendly technologies.
A unit of solar energy on average now costs 85% less than it did in 2010, while wind power is now 55% cheaper. The cost of lithium-ion batteries, used in electric vehicles, also fell steeply.
In some countries, policies have led to increased renewable energy and electric vehicle use, or have slowed the rate of deforestation.
CHALLENGES REMAIN
The report also weighs in on how market and regulatory tools can help stimulate innovation and technological competition, two strategies for boosting incentives to cut emissions. For example, removing fossil fuel subsidies and introducing carbon pricing would direct more investment toward renewable solutions.
In the agriculture sector, growing crops within forests and managing livestock more sustainably would help improve land productivity and resilience to climate impacts such as heat or drought.
Some climate-friendly options face significant hurdles, such as public resistance to nuclear power or to costly carbon-removal technologies.
Still, global finance for climate technology and solutions is far short of where it needs to be for curbing emissions enough to limit warming to 1.5 degrees C.
Original source: Reuters
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