How sea-salted clouds, solar and social influencers could help with climate change
Only immediate, climate action will keep global temperatures from rising 1.5 degrees, report says
While the latest report by the Intergovernmental Panel on Climate Change (IPCC) laid out, yet again, some dire predictions about the planet unless immediate action is taken, the United Nations experts also offered a glimmer of hope.
Only immediate, ambitious climate action will keep global temperatures from rising 1.5 C — a benchmark agreed to in the 2015 Paris Agreement — said the report, released Monday. Otherwise there could be some extreme climate change with severe impacts on people, wildlife and ecosystems.
Yet there are solutions that could make a difference, the report suggests.
"Having the right policies, infrastructure and technology in place to enable changes to our lifestyles and behaviour can result in a 40-70 per cent reduction in greenhouse gas emissions by 2050," Priyadarshi Shukla, co-chair of IPCC Working Group III, and a professor at the Indian Institute of Management Ahmedabad who specializes in energy and environment modelling and policies, said in a news release.
"This offers significant untapped potential," to reducing the overall rise in global temperatures.
Sucking CO2 from the atmosphere
Global warming is caused by too much carbon dioxide being released into the atmosphere by human activities. Removing it is important to fighting climate change. Indeed, the IPCC's report says carbon dioxide removal is key to limiting warming to 2 C or 1.5 C. This can be done by through methods which include reforestation, ocean fertilization and "enhanced weathering" — the process of spreading crushed rock over large areas.
CO2 could also be removed through technology like direct air capture with carbon storage (DACCS) which use chemical processes to separate and store CO2.
However, the effectiveness of DACCS has been and some critics say such CO2 removal may undermine incentives to switch from fossil fuels.
Sea salt in clouds? Pumping aerosols into the sky?
The IPCC report also looked at proposals to increase the reflection of solar radiation back into space. It says solar radiation modification (SRM) cannot be the main policy response to climate change and is, at best, a supplement to the larger goal of achieving sustained net zero CO2 emission levels globally.
Some proposed SRM methods include:
- Injecting reflective aerosol particles, or a gas which converts to aerosols, directly into the stratosphere.
- Spraying sea salt or other particles into marine clouds, making them more reflective.
- Whitening roofs and covering glaciers with reflective sheeting.
However, the IPCC says in its report that "their potential to reduce risk or introduce novel risks … is not well understood."
Switching to solar and wind energy as costs drop
Changing to renewable sources of energy could be much easier now because the unit costs for solar, wind and batteries have dropped rapidly over the last four years, according to the report.
For example, from 2015 to 2020, the costs of solar- and wind-generated electricity dropped 56 per cent and 45 per cent, respectively, while battery prices dropped by 64 per cent, according to the report. As well, in many contexts, solar and wind power are now competitive with fossil fuels, the report said.
Electric vehicles
Electric vehicles are the fastest growing segment of the automobile industry, according to the report and, along with electric public transit vehicles, can significantly reduce emissions, the report says.
The rich can help, and social influencers too
While those are wealthy contribute disproportionately to higher emissions, they could also become role models of low-carbon lifestyles, by, in part, investing in low-carbon businesses and advocating for stringent climate policies, the report says.
Social influencers and thought leaders can also increase the adoption of low-carbon technologies, behaviours and lifestyles, it said.
With files from The Associated Press, Reuters