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I’ve been reading agroforestry and permaculture books for a while — I’d love to get into farming —, and this has been known for ages. Even if not fully underst
by xctr94 3y ago
I’ve been reading agroforestry and permaculture books for a while — I’d love to get into farming —, and this has been known for ages.
Even if not fully understood, it’s well known in agro that trees raise the humidity level of an area and create micro-climates that increase the amount of rain (e.g. of doing nut trees in a valley).
I think… modern agriculture just forgot/ignores ancient knowledge.
- philipov 3y agoAre you telling me the Rain Follows The Plow folks were actually on to something?
- mooreds 3y agoSolid joke :) . Unfortunately, you typically don't plant trees with a plow.
- the_third_wave 3y agoActually you do, at least when planting on a large scale. A planting plough is pulled behind a tractor, the device opens a furrow into which seedlings are dropped at a regular interval by someone riding the plough or mechanically. The furrow is closed with the top of the seedling sticking out. Here's how you can convert an old plough to a tree planting plough: https://core.ac.uk/download/pdf/228205053.pdf https://core.ac.uk/download/pdf/228205053.pdf
- brnaftr361 3y agoI bet there's folk tales that parallel it with angry forest spirits, too. Explaining the unknown with anthropomorphization.
- Avshalom 3y agolocal humidity levels is just transpiration, which yeah in a valley trapping the humidity can create rain but that's not the same as this cloud seeding mechanism.
- steve_adams_86 3y agoWithout a doubt, and it’s well known in urban planning and landscaping too. But in a discussion about why industry might be harmful, not having facts to back yourself up makes your case effectively irrelevant. Even pointing to countless reforestation projects with heaps of positive precipitation and hydrological data is no help; as long as the mechanism isn’t clear, people who want to maintain business as usual will not listen. So, information like this is a huge help and a step towards having a more crystallized picture of why forests are crucial to hydrology.
- dr_dshiv 3y agoTerpenes from trees also produce OH which converts methane to CO2. No idea whether this has a big effect, but I find it fascinating.
- aeroman 3y agoThe increase in humidity is actually a different effect - evapotranspiration from trees is included in climate models (along with their response to increasing CO2 concentrations) [0]. The effect in this article is more to do with the particulates that form from the chemical emitted from trees. The article doesn't make it clear, but an increase in tree particulates (known as aerosols) would actually cause less rain. Almost all cloud droplets form on an aerosol particle, so the cloud droplets in a cloud with more aerosols are on average smaller (as the water is spread out over more droplets). These smaller droplets take longer to grow large enough to form rain, an effect which is thought to decrease the amount of precipitation in some regions (although by a small amount). This effect is also included in climate models, but the sources of aerosol (such as from trees) are more uncertain [1], producing the uncertainty in future climate projections. [0] - https://gmd.copernicus.org/articles/4/677/2011/gmd-4-677-2011.pdf https://gmd.copernicus.org/articles/4/677/2011/gmd-4-677-201... [1] - https://www.nature.com/articles/nature12674 https://www.nature.com/articles/nature12674
- Loughla 3y agoModern agriculture didn't forget. It chose differently because quantity is the only measure of success. Trees causing rain has to be substantially less efficient in the short term than irrigation.
- steve_adams_86 3y agoThe trouble is that reduced forest leads to reduced rain, and irrigation often reduces ground water which is replenished even slower than before. It accelerates water losses a lot faster than anyone expected.
- Loughla 3y agoYes, but that is a different problem than immediate water availability for crop use.
- xctr94 3y agoI agree that irrigation needs are urgent. However, we also need incentives towards an eventual transition. A basic example: contours to mitigate how fast water moves in elevated terrain. Cheap and effective. Then water collected at dug basins in the bottom. If you have cheap, constant access to water, you irrigate industrially. It’s only when droughts, lack of groundwater, climate effects, etc. kick in that the alternatives become important. But by then, you didn’t put them in place early enough. So I think farming deserves both short- and long-term thinking. Business as usual won’t work as climate conditions get worse.
- Loughla 3y ago> basic example: contours to mitigate how fast water moves in elevated terrain. Cheap and effective. Then water collected at dug basins in the bottom. Before I respond, I have another question: Are you saying this is something we are not doing and should be?
- lrem 3y agoIt's almost as if farmers were inclined to borrow water from their descendants some centuries down the line, isn't it?
- agumonkey 3y agoIf you have a reading list to suggest, i'm all ears.
- xctr94 3y agoI’ve lots on my e-reader, but I keep going back to Ben Falk. “The Resilient Farm and Homestead” is super cool, you actually follow their story over multiple years, with the farm’s changes rather well documented! Of course the more scientific books on the topic are better information-wise — some used at uni —, but Falk’s is nice to read.