I’ve looked at clouds from both sides now
From up and down, and still somehow
It’s cloud illusions I recall
I really don’t know clouds at all
~ Joni Mitchell
Climate change is bringing worrying uncertainty to our weather patterns. We try to minimize or eliminate carbon emissions to reduce the greenhouse effect, but we’re taking too little action too late. Lacking the nerve to really reduce our energy use, we’re focusing on alternative power sources to reduce our use of coal, oil and natural gas. Solar power appears to be the best alternative power source, but there always seems to be a cloud on the horizon.
Do we want more sun or more clouds?
Reporting on a recent study, Elizabeth Waddington writes, “Clouds are notoriously difficult to study and have been largely discounted from many of the studies that have looked into afforestation, reforestation, and natural climate change mitigation in the past. Clouds, however, have a cooling, if transitory, effect on the Earth. They directly block the sun, but also have a high albedo, similar to ice and snow. They reflect more sunlight and therefore have a cooling effect. “
The researchers reported that “climate models underestimate the cooling effect of the daily cloud cycle. They also reported last year that climate change could result in increased daily cloud cover in arid regions like the American Southwest … Clouds form more frequently over areas of forest than they do over grasslands and other areas with short vegetation. This study found that clouds tend to form earlier in the afternoon over forested areas, which means clouds are in place for longer and have more time to reflect solar radiation away from the Earth … When this is taken into account, the cooling effect from the clouds, in combination with the carbon sequestration of the forests themselves, outweighed the solar radiation absorbed by forests.
This puts a different spin on the old saying, “Rain follows the plow.” Seems like rain follows the trees.
Journalist Bianca Nogrady reported, “Around half of the excess carbon dioxide that is released into the atmosphere by human activity — the combustion of fossil fuels — is ‘drawn down’ again by natural processes: half by land-based processes — mainly plants — and half by the oceans … The fact remains, though, that trees are carbon guzzlers. Around half the mass of a single tree is pure carbon. Given that forests cover 31 per cent of global land area — around 4 billion hectares — that’s a lot of stored carbon.”
Tree planting is good for us and the planet. Norgrady continues, “There are already numerous initiatives underway around the world to plant trees. For example, the Bonn Challenge aims to reforest 350 million hectares of degraded and deforested landscapes by 2030, and has already achieved 150 million hectares of reforestation in countries such as Brazil, Burkina Faso, India and Cameroon. One study has estimated that 0.9 billion more hectares of forests could be grown on existing viable land that isn’t already occupied by forests, agriculture or urban areas, and that these could store 205 gigatonnes of carbon — the equivalent of around one-quarter of the carbon dioxide currently in the Earth’s atmosphere.”
Trees sequester carbon and bring rain. Increased moisture and cooling can have negative effects, too. Nogrady observes, “Despite these concerns and limitations, given the incredible number of ecosystem services that trees provide to humanity — clear air, water, soil stability, oxygen, shelter, food and building materials — reforestation can only improve our environmental conundrum, not worsen it.”
Go plant trees!
Joni Mitchell, Both Sides Now, September 16, 1967
Bianca Nogrady, We’ve Got Carbon Capture All Wrong, April 6, 2021, WIRED
Elizabeth Waddington, Planting Forests at Mid-Latitudes Could Help Cool Planet, August 27, 2021, TreeHugger