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Why are Pakistan’s floods so extreme this year?

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Re: Why are Pakistan’s floods so extreme this year?

#131

Post by ok_dad »

bmismyname wrote: post #80

Higher temperatures mean more moisture in the atmosphere and aridification at the same time. That's why there can be drought plus record breaking rainfall at the same time. Plus, when you have drought, it damages the soil and plant life which would normally aid in capturing and retaining the rainfall. And when the rain does fall, instead of being absorbed into the soil it just creates erosion instead as the top layer…

Crazy to think we might actually kill the soil. Imagine a place like mars, because of the soil dies so will everything else.

Re: Why are Pakistan’s floods so extreme this year?

#132

Post by carapace »

peteradio wrote: post #55
Panino wrote: post #36

Earlier quoted context omitted.

When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen. I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan,…

Any link to read about this 0.5 - 30 inch/hr conversion? Cultivated soil or already wetted soil will absorb much more readily than not, was this a carefully controlled experiment? Anyway it would take some serious modelling not handwavy yes or no as to whether permaculture/regenerative techniques (and a well defined definition of success of mitigation) could work. I absolutely admit that it could help on the margins,…

Check out: Treating the Farm as an Ecosystem with Gabe Brown Part 1, The 5 Tenets of Soil Health https://www.youtube.com/watch?v=uUmIdq0D6-A

His neighbor's farm floods, his land soaks it up like a sponge.

Year-on-year his topsoil gets deeper.

Re: Why are Pakistan’s floods so extreme this year?

#133

Post by hedora »

Panino wrote: post #36
peteradio wrote: post #15

Earlier quoted context omitted.

Sounds ridiculous on its face, and that is as a practitioner of permaculture. I couldn't really get my head around how it could possibly make even a slight dent against the massive flooding witnessed here.

When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen. I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan,…

Water infiltration is measured by digging a small hole, filling it with water, and seeing how fast it drains. There's no way that regenerative agriculture has changed soil composition multiple feet down, which is what would be needed for the soil to absorb multiple feet of water.

I went to check the above sentence, and the first hit was this detailed article from Washington State, which analyses Brown's claims in detail, and explains why the scientific community is skeptical of them:

https://csanr.wsu.edu/regen-ag-solid-principles-extraordinar...

Anyway, even if, as Gabe Brown claims, regenerative agriculture is an order of magnitude more effective than expected, and you applied it to 100% of the land in Pakistan, it would still only reduce flooding by less than a foot.

Re: Why are Pakistan’s floods so extreme this year?

#134

Post by mountaintimefrm »

CommanderData wrote: post #10

I read someone else suggest Permaculture as a way of mitigating some of the affects of monsoons in these types of areas. Does anyone have any evidences of such a thing working?

Probably the best documented example of it working is in the Loess Plateau in China. John D Liu has a couple documentaries on it, here is one: https://youtu.be/IDgDWbQtlKI

A good example of a similar project in India, as covered by Andrew Millison: https://youtu.be/jDMnbeW3F8A

Sepp Holzer did a similar project in Portugal: https://www.youtube.com/watch?v=OUryneCjxV4 ...I believe he also did some pretty large projects in the middle east, but I can't find any vids on them at the moment.

Geoff Lawton has done a ton of projects like this, but maybe not at the landscape wide scales like the projects above.

Probably the best book on the basic principles of how to do it - Rainwater Harvesting for Drylands and Beyond by Brad Lancaster. Also the book Water For Every Farm by P.A. Yeomans is pretty good as well, but not as accessible of a read.

TLDR - To keep desert monsoons from flooding areas downstream, dig a landscape wide network of swales and basins to catch, soak and sink the water into the soil. Properly dug, such earthworks recharge aquifers while stopping flooding and erosion.

Re: Why are Pakistan’s floods so extreme this year?

#135

Post by throw_nbvc1234 »

snewman wrote: post #125
rad_gruchalski wrote: post #44

Earlier quoted context omitted.

> At least a single volcanic eruption is not enough to change the long-term climate trend, you need a clusters of eruptions to persist through centuries for that. https://en.m.wikipedia.org/wiki/1883_eruption_of_Krakatoa “ The eruption caused a volcanic winter.[17] In the year following the eruption, average Northern Hemisphere summer temperatures fell by 0.4 °C (0.72 °F).[18] The record rainfall that hit Southern Ca…

GP said "long-term climate trend" and then mentioned centuries. Yes, an especially large eruption can influence things for a year or two. But then the effect settles out.

Well this flooding is occurring 8 months after the eruption mentioned so it seems a reasonable question to ask.

Re: Why are Pakistan’s floods so extreme this year?

#136

Post by worik »

hedora wrote: post #133
Panino wrote: post #36

Earlier quoted context omitted.

When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen. I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan,…

Water infiltration is measured by digging a small hole, filling it with water, and seeing how fast it drains. There's no way that regenerative agriculture has changed soil composition multiple feet down, which is what would be needed for the soil to absorb multiple feet of water. I went to check the above sentence, and the first hit was this detailed article from Washington State, which analyses Brown's claims in det…

> . There's no way that regenerative agriculture has changed soil composition multiple feet down

How do you know that?

How deep do roots go? Do worms dig? Do you know?

I do not. But I am not making assumptions

Re: Why are Pakistan’s floods so extreme this year?

#137

Post by mountaintimefrm »

Panino wrote: post #36
peteradio wrote: post #15

Earlier quoted context omitted.

Sounds ridiculous on its face, and that is as a practitioner of permaculture. I couldn't really get my head around how it could possibly make even a slight dent against the massive flooding witnessed here.

When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen. I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan,…

Gabe Brown's work is primarily on improving soil health, not on earthworks for flood prevention, aquifer recharge, etc. His gains in rainwater infiltration is a secondary effect of the steps he's taken to improve his soil.

In terms of projects whose primary aim is flood prevention / aquifer recharge, John D. Liu, Andrew Millison, and Geoff Lawton all have documented quite a few projects that have been very successful in addressing the problem.

Re: Why are Pakistan’s floods so extreme this year?

#138

Post by time_to_smile »

ageofwant wrote: post #24
time_to_smile wrote: post #3

I think it's worth pointing out that the impacts of climate change are often presented as singular effects: rising sea level, warmer summers, increased drought, etc. But as we can see here there is also a very strong interaction effect between all of these (and it tends to magnify the issues rather than having them cancel out). This is also why many major climate reports tend to inherently be on the conservative side…

Pretty disheartening to see the downvotes in a forum like hn which are supposed to be informed about these things. If people that are supposed to be able to critically assess data and have access to as much information they need to verify any claims come to the conclusion that you are full of shit, what hope is there to educate grandpa screaming at the wokes on the street.

HN has become very hostile to reality when reality makes people scared.

I no longer expect any thing I say to convince people, but still keep saying what I do so that other people that see it, can feel a little less crazy/alone.

Consider it my, probably futile, struggle against the upcoming wave of cognitive dissonance. As soon as I realized the way things were headed, I also realized that, paradoxically, the more obvious our situation becomes the more aggressively people will refused to see it.

There was a time on HN where downvotes where pretty exclusively reserved for trollish comments and other inappropriate content. I agree with your feeling that this is disheartening, but strangely serves as evidence that these things are happening.

I myself have days where I can't believe my own eyes as I watch events unfolding I thought I would only see at the end of my life if I lived to a ripe old age.

Re: Why are Pakistan’s floods so extreme this year?

#139

Post by worik »

joshuajill wrote: post #73
Panino wrote: post #36

Earlier quoted context omitted.

When Gabe Brown switched from conventional agriculture to regenerative agriculture, he increased water infiltration in his soil from 0.5 inches (1.25cm) per hour to 30 inches (75cm) per hour. So imagine if he and all his neighbors had the same beautiful soil -- flooding just couldn't happen. I haven't seen a list of such measurements from permaculture, but I know it can be used to regreen deserts (as shown in Jordan,…

Maybe even relatively simple but massive reforestation efforts could help mitigate climate change effects in the long run.

Forests are not very good carbon sinks except in the short run.

They have three problems when used as carbon sinks:

1) They tie up land for one, otherwise, non productive purpose (the wild species living in them do not mind that, must be said)

2) Once fully grown they reach a carbon balance. This can happen surprisingly quickly, a few decades.

2) Forests do not simply sit there like a rock. Eventually they will burn unless managed. Then they simply release all that stored carbon into the atmosphere.

Regenerative agriculture is a much better carbon sink. The process of storing the carbon increases the soil fertility so it is a win/win. Soils can get very deep so there is not a natural limit like for forests.

A draw back is measuring the carbon sunk. I do not know of anybody doing that (a market opportunity?). An important part of carbon farming is selling the "carbon credits" (a mad bad and sad idea, but it is a thing) to do that there must be an accepted measure of carbon sequestration, like there is for trees.

Re: Why are Pakistan’s floods so extreme this year?

#140

Post by snewman »

throw_nbvc1234 wrote: post #135
snewman wrote: post #125

Earlier quoted context omitted.

GP said "long-term climate trend" and then mentioned centuries. Yes, an especially large eruption can influence things for a year or two. But then the effect settles out.

Well this flooding is occurring 8 months after the eruption mentioned so it seems a reasonable question to ask.

Ah, fair. A single eruption will not perturb the long-term trend, but we're discussing the short-term incident in Pakistan, and a single eruption can have notable short-term impact. (I don't know anything about whether the specific eruption in question could have any impact on this specific crisis in Pakistan.)
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