[HN Gopher] Why are Pakistan's floods so extreme this year?
___________________________________________________________________
Why are Pakistan's floods so extreme this year?
Author : pseudolus
Score : 139 points
Date : 2022-09-02 13:09 UTC (9 hours ago)
(HTM) web link (www.nature.com)
(TXT) w3m dump (www.nature.com)
| time_to_smile wrote:
| 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: it's really, really hard to correctly
| model these interactions so you can only earnestly report the
| predicted change in individual variables rather than the impact
| on the system.
|
| And keep in mind this is not the "new normal", we're entering a
| period of transition that will not end within our life times. The
| rate of CO2 accumulating the atmosphere is accelerating and the
| rate of methane in the atmosphere is rapidly accelerating. We
| will likely see a blue ocean event in the next 20 years and it's
| really hard to imagine how that will even play out with the
| global climate, Thwaites glacier could collapse without much
| warning (very rapidly causing sea level rise beyond our current
| projections), the AMOC slow down could reach a tipping point,
| etc.
|
| Everything we're witnessing now will in the future seem
| relatively mild.
| alexose wrote:
| It's not a foregone conclusion that we're doomed to a life of
| accelerating climate change. We could deploy solar
| geoengineering to see us through the transition to renewables.
| Then, as fossil sources are retired and direct air capture
| comes online, gradually draw down our geoengineering efforts.
|
| It may seem like a non-starter right now, but what about five
| years from now? What if our best climate models agree that it
| will do less damage to the planet than allowing the permafrost
| to thaw?
| AftHurrahWinch wrote:
| I think it's a political problem, not a technical problem. If
| we can imagine that our best climate models could drive
| decision making to enable geoengineering... why don't our
| best climate models drive earlier interventions?
| alexose wrote:
| Geoengineering is a unique prospect in that it's
| inexpensive-- Cheap enough that a couple of billionaires
| could pay for it if they wanted. In terms of interventions,
| it's a much easier pill to swallow than something in the
| trillions of dollars.
|
| The pushback comes from the risk. While we know that it'll
| cool the planet, we don't necessarily know how it'll affect
| weather patterns. If we can figure that out with some level
| of certainty, I believe there will be a point where the
| rewards outweigh the risks.
| AftHurrahWinch wrote:
| I think there are probably several billionaires who
| independently have the resources the pursue significant
| stratospheric aerosol injection. I wonder how such an
| individual would imagine their liability for stochastic
| effects on agriculture. Those risks make me think it's
| most likely a government with a nuclear arsenal would
| pursue this... perhaps India? Mumbai could become a very
| difficult place to live in a few decades.
| bena wrote:
| I had to look up what a "blue ocean event" was. So, for others,
| here it is:
|
| https://en.wikipedia.org/wiki/Arctic_sea_ice_decline#Impacts...
| 88840-8855 wrote:
| jibe wrote:
| How about not shutting down German nuclear plants, and not
| buying "clean natural gas from mother russia".
| 88840-8855 wrote:
| Beep boop. Not a Russian bot, a German one who is just
| pissed of by the current politics and the elitist
| decisions.
|
| And I hate it that any alternative proposed to the current
| kamikaze politics is called "Russian bots".
|
| Yes, German nuclear plants was yet another trash decision
| and pushed again by the fear agitated by the Green Party.
| And yet, the majority wants nuclear, the Greens are against
| it.
|
| We need REALPOLITIK and not this ideological trash. And
| REALPOLITIK to beat the biggest thread: global warming...
| and not some random conflicts between random countries
| nobody cared about 7 months ago and some random old pseudo-
| dictators that will anyway not be alive in a few years
| anymore.
| jibe wrote:
| Get natural gas from Canada and the US. North America can
| supply Europe. Frack in Germany, supply yourself.
|
| You have to choose, is Ukraine worth short term financial
| pain? The choice is to surrender Ukraine to Russia and
| take the gas, or suffer for a year financially while you
| ramp up other energy sources.
| barbazoo wrote:
| Is there such a thing as "clean gas" and if so, how does
| Russian gas qualify here?
|
| Also, isn't it Russia that's throttling gas delivery to 20%
| right now?
| 88840-8855 wrote:
| barbazoo wrote:
| Russia invaded Ukraine. What did the EU do to justify
| this? I don't mean what Russia's reasons are (NATO
| expansion) but what morally justifies it.
| mc32 wrote:
| Highlighted by the stupidity of not buying directly from
| Russia at normal prices but instead buying the same
| hydrocarbons extracted by Russia from war washing third
| parties like China and India who resell Russian hydrocarbons
| to those who for political reasons can't buy directly but can
| buy indirectly at inflated prices!!
|
| It's the height of stupidity.
| barbazoo wrote:
| As far as I can tell, e.g. (1), the EU does not get gas
| from China or India.
|
| (1) https://markets.businessinsider.com/news/commodities/eu
| ropea...
| 88840-8855 wrote:
| There you go
|
| https://www.ft.com/content/1e20467a-5b53-42b7-ad89-49808f
| 7e1...
| barbazoo wrote:
| You're right it seems. Here's a non-paywalled article
| https://news.yahoo.com/china-reselling-natural-gas-
| energy-14...
| unmole wrote:
| https://www.vortexa.com/insights/products/indias-diesel-
| expo...
| ageofwant wrote:
| 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.
| time_to_smile wrote:
| 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.
| mempko wrote:
| I love technology and have to keep telling my friends that
| it's possible there won't be a computer industry in 30 years.
| I'm not joking. Our technology requires a highly complex and
| organized society to continue to function and develop.
| Complex and highly organized societies developed under a
| stable climate. We created societies built on cities that
| don't move.
|
| If you love technology. If you love computers. Then global
| warming is your biggest threat and something you should care
| about deeply.
| Sharlin wrote:
| It is difficult to get a man to understand something when his
| startup idea depends upon his not understanding it.
|
| -Upton Sinclair, paraphrased
| notabee wrote:
| It's not surprising, actually. The problem with very smart
| people is that they're often very smart in their particular
| domains of expertise, but socially they will be treated as
| just very smart in general. This often leads to an emotional
| overconfidence in assessing fields outside their domains of
| expertise, and that extreme cleverness becomes more of a tool
| to create complex rationalizations of uninformed biases
| rather than being used humbly, empirically, and diligently as
| should be the case for a beginner in any topic.
|
| And yes, I'm aware that's essentially a paraphrase of the
| Dunning-Kruger concept. We're all probably making similar
| assumptions about domains of knowledge we don't know much
| about, because that's what the brain does. Just like human
| vision appears solid and complete but is actually a stitched
| together amalgamation of the small, receptor-dense fovea in
| the center darting around constantly, and the rest being
| filled in by the brain instead of direct perception, so is
| our impression of the world, and we won't know things for
| sure unless we take time to study them up close.
| hotpotamus wrote:
| Yeah, but it's possible that all that might not happen, so we
| probably shouldn't worry about it. You wouldn't want to have to
| buy a smaller vehicle would you? People would think you were
| effeminate.
| polygamous_bat wrote:
| I believe this is one of the largest challenges when trying
| to make effective changes in the system to address climate
| change: those whose actions can create the largest changes
| are not the ones who have to bear the burden first or
| directly. I really don't know how to appeal to a crowd
| denying all the evidence, so devoid in empathy for people
| across the world, while, as an immigrant, I can see my
| neighboring countries literally drowning.
| buscoquadnary wrote:
| > I believe this is one of the largest challenges when
| trying to make effective changes in the system to address
| climate change: those whose actions can create the largest
| changes are not the ones who have to bear the burden first
| or directly.
|
| You mean the corporations and companies that continue to
| produce emissions on a massive scale while trying to
| constantly shame me and tell me what a bad person I am for
| having the audacity to drive to the grocery story once a
| week or so?
| hotpotamus wrote:
| That's an aspect, but the thing I find the most maddening
| is that people cast doubt on the science by saying that the
| effects of changing the mixture of gasses in our atmosphere
| are ultimately not completely knowable. That's obviously
| true, but to me that's all the more reason why we probably
| should avoid doing it as much as possible.
| hackerlight wrote:
| I am certain that's part of the psychology. Wealthy people
| in the colder north know that even if shit hits the fan in
| poorer and hotter countries, they can pull up the draw
| bridge and still survive, despite being the people that
| caused the situation. It's like a long slow genocide
| perpetrated by a billion people.
| marcosdumay wrote:
| > The rate of CO2 accumulating the atmosphere is accelerating
|
| It's a small point, but the ratio of CO2 on the atmosphere is
| definitively not accelerating. On the last couple of decades it
| has been growing steadily, and the noisy few months look like
| they have negative acceleration.
|
| https://climate.nasa.gov/vital-signs/carbon-dioxide/
| barbazoo wrote:
| I chuckled when I saw your username together with your probably
| not far fetched but damning prediction of what's to come.
| eldaisfish wrote:
| also missing is yet another aspect of a very complex system -
| parched soil has lower ability to retain water. These floods
| follow an intense heatwave during which large swathes of
| pakistani soil dried up. Come the rains and you have a massive
| problem.
|
| Like you say, this is just the beginning. If floods like this
| happen in the Indian plains - and they will - the human and
| social costs will be immense.
| dylan604 wrote:
| we just saw this in the DFW area last week. 3 months of
| triple digit temps and zero precip followed by a single 24
| hour period receiving 5-7" of rain. the ground was so hard,
| that it might as well have been concrete. that just allowed
| all of the water to run off into the streams that fed the
| lakes. fortunately, those lakes were well below normal
| levels, so this just helped them come back to where they
| were. if there were multiple days of that level of rain, a la
| Harvey, we'd have been really screwed.
| ErikVandeWater wrote:
| I'd love to see nature write an article about why a certain part
| of the world has had such unusually moderate temperature and
| precipitation of late. Also, if you want to search the whole
| globe for something extreme happening, you're guaranteed to find
| it in spades.
| bosswipe wrote:
| Here's what the temperature anomaly looks like for "the whole
| globe" https://www.youtube.com/watch?v=haBG2IIbwbA
| jamiek88 wrote:
| What does this even mean? Are you denying that climate change
| is a thing? Now? In 2022?
| wahnfrieden wrote:
| waiting for absolute apocalypse before taking up a curious
| mind about it
| nyc_data_geek1 wrote:
| A sadly prevalent line of rhetoric here on HN. We could be
| living on venusian Earth and some HN pedant would be
| splitting hairs
| esperent wrote:
| For example, if you search through the whole globe for people
| holding extreme anti-science views denying climate change in
| the face of overwhelming evidence, you'll find literally
| millions of them.
| prpl wrote:
| no mention of the Hunga Tonga-Hunga Ha'apai eruption?
|
| It sounds like that eruption at least changed atmospheric
| composition by throwing tons of water into it.
| bagels wrote:
| Do you have any sources that discuss this?
| morsch wrote:
| _The undersea eruption also ejected 146 million tons of South
| Pacific Ocean water into the stratosphere.[56] The amount of
| water vapor ejected was 10 percent of the atmosphere 's
| typical stock.[57] It was enough to temporarily warm the
| surface of Earth. This water vapour was estimated to remain
| for 5-10 years.[55]_
|
| https://en.wikipedia.org/wiki/2022_Hunga_Tonga%E2%80%93Hunga.
| ..
| bagels wrote:
| Thanks for sharing this. That certainly is a lot of water.
| throwaway7980 wrote:
| munk-a wrote:
| Wikipedia is generally a great summarization of a topic
| and links to numerous sources - that is usually a more
| valuable thing to link than an opaque research paper.
| selectodude wrote:
| You could always click on the source that Wikipedia has
| literally next to the sentence.
|
| https://www.nature.com/articles/d41586-022-01544-y/
| rad_gruchalski wrote:
| The sources are in footnotes. The quote even contains
| footnote references.
| sebazzz wrote:
| Interesting as water vapour is in itself also a greenhouse
| gas.
| ancientworldnow wrote:
| Here's a practical examination of what effect the 10%
| increase in stratospheric water vapor caused by the eruption
| has on global weather: https://www.severe-weather.eu/global-
| weather/cold-anomaly-st...
| Comevius wrote:
| https://link.springer.com/article/10.1007/s00376-022-2034-1
|
| Unlikely. 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. HTHH will
| likely decrease the global mean surface temperatures by
| 0.004degC in the first year.
|
| Compared to that human activity is a thousand times more
| significant, everything else is statistical noise next to it,
| which at least means that it is easy to spot.
| rad_gruchalski wrote:
| > 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 degC (0.72 degF).[18] The record
| rainfall that hit Southern California during the water year
| from July 1883 to June 1884 - Los Angeles received 970
| millimetres (38.18 in) and San Diego 660 millimetres (25.97
| in)[19] - has been attributed to the Krakatoa eruption.[20]
| There was no El Nino during that period as is normal when
| heavy rain occurs in Southern California,[21] but many
| scientists doubt that there was a causal relationship.[22]
|
| The eruption injected an unusually large amount of sulfur
| dioxide (SO2) gas high into the stratosphere, which was
| subsequently transported by high-level winds all over the
| planet. This led to a global increase in sulfuric acid
| (H2SO4) concentration in high-level cirrus clouds. The
| resulting increase in cloud reflectivity (or albedo)
| reflected more incoming light from the sun than usual, and
| cooled the entire planet until the sulfur fell to the ground
| as acid precipitation.[23] ".
|
| Yes, I'm aware of "but many scientists doubt that there was a
| causal relationship" regarding the rain but the climate has
| been affected by a single eruption.
| [deleted]
| snewman wrote:
| 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.
| throw_nbvc1234 wrote:
| Well this flooding is occurring 8 months after the
| eruption mentioned so it seems a reasonable question to
| ask.
| snewman wrote:
| 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.)
| booi wrote:
| Also https://en.wikipedia.org/wiki/Year_Without_a_Summer
| with Mount Tambora
|
| There's good evidence this has happened multiple times in
| history by a single eruption.
| Comevius wrote:
| That was the consequence of at least two eruptions, one
| of which emitted up to 60 Tg of sulphur dioxide. HTHH
| only emitted 0.4 Tg.
|
| It is not impossible that HTHH affected the monsoon, but
| there is a thousand pound elephant in the room that will
| make it's effect hard to quantify.
| kurupt213 wrote:
| Human activity is responsible for less than 5% of greenhouse
| gasses. One eruption can spew decades worth of gases into the
| air
| Comevius wrote:
| This is misinformation. Volcanoes are responsible for less
| than 0.5 Gt of the global CO2 emissions a year. That's a
| bit less than the 50 Gt we are responsible for. Volcanoes
| and solar flares would have caused a slight cooling in the
| last 100 years, not a sharp warming we are experiencing.
|
| There is a natural carbon cycle, which is quite balanced in
| that there is barely any radiative forcing, which is the
| difference between how much energy enters the atmosphere
| and how much of it leaves. Human activity amounts to all, I
| repeat all of the radiative forcing in the last century,
| and more actually, because naturally there would have been
| negative forcing.
| ben_w wrote:
| Not directly, though I can't guess at indirect effects. If 100%
| of the water from that landed in the flooded area of Pakistan,
| it would've only added 2.6 mm:
|
| http://www.wolframalpha.com/input/?i=146%20million%20cubic%2...
| prpl wrote:
| I had only been alluding to indirect effects - an increase in
| the greenhouse effect, which certainly would raise
| temperatures (and increase the amount water air can hold).
|
| I think we will find that, even during an increase in
| anomalous years from climate change, 2022-2023 will be
| anomalous.
| [deleted]
| ben_w wrote:
| In that case I certainly wouldn't be surprised either way.
| IIRC the altitude of the water makes a difference.
| rr888 wrote:
| Reminder that population is Pakistan's population 6x it was at
| 1950. In 2050 its expected to be 370 million people compared to
| 37 million in 1950.
| https://en.wikipedia.org/wiki/Demographics_of_Pakistan
| hh3k0 wrote:
| I'm going to go out on a limb here and say that Pakistan's
| population in 2050 will be closer to 37 million than to 370
| million.
| onlyrealcuzzo wrote:
| This sounds extreme, but it's not as extreme as everyone
| seems to think.
|
| 200M is closer to 37M (+163M) than 370M (-170M).
|
| OP is saying a 10% decrease is more likely than the
| population staying even.
|
| I disagree - but not as wildly as I would if OP was saying
| that the population is likely to actually be close to 37M.
|
| 200M is quite far from 37M... It's just that 370M is even
| farther...
| oefnak wrote:
| I find it more logical think of orders of magnitude, so to
| compare numbers by dividing them; with 100 sitting between
| 10 and 1000. Then 200 is a lot closer to 370 than to 37.
| okaram wrote:
| Current pop is 220M, already closer to 370 ... I can see it
| not growing much, but not decreasing.
| rr888 wrote:
| Nukes?
| miohtama wrote:
| There is not simply enough food and energy
| o_m wrote:
| The population of a country peaks a few years after it has
| gotten developed. As in low child mortality, high educated
| population, etc.
| CydeWeys wrote:
| What countries do you think this is true of? Even, say,
| France is still growing. Let alone the US.
| highwaylights wrote:
| US birth rate: 1.70 France birth rate: 1.87 Japan birth
| rate: 1.36 Pakistan birth rate: 3.45
|
| So Pakistan, unlike many more developed countries, has a
| birth rate higher than the replacement rate, but
| significantly lower than it's 1950 to 2000 highs over 6 -
| and trending downwards.
|
| The population would be expected to drop precipitously,
| but not soon.
| [deleted]
| meowtimemania wrote:
| Are those countries growing with birth rates alone? I
| thought immigration was what was helping the populations
| stay stable
| pornel wrote:
| The extent of the flood is massive:
| https://static.dw.com/image/62963931_7.png (source:
| https://www.dw.com/en/pakistanis-outraged-by-inept-governmen...)
| Erlangen wrote:
| The scale of the flood is crazy. Since the image data is
| sourced from UNOSAT, I found out more updated data from its
| website: https://unosat.org/products/
| jmyeet wrote:
| While it's absolutely true there is a confluence of factors here
| (eg glacial melt, heat wave and a depression) and that these
| events are more likely with global warming, I'm disappointed this
| article didn't cover another important factor: dams.
|
| Flooding used to be a much bigger problem in the Western United
| States and it was solved with dams. Yes, there is thd risk of dam
| failure but we're weighing up the real and present risk of
| flooding regardless against the possible risk of dam failure.
|
| Unfortunately, there has been increasing opposition from the
| environmental lobby against building dams in the developing world
| in recent decades (eg [1]) and this matters when such countries
| are usually dependent on the World Bank and/or IMF to fund their
| construction.
|
| Dams not only reduce the risk of extreme flooding but also
| provide cheap hydroelectric power, which is of incredible value
| to a developing nation.
|
| Pakistan has some dams but clearly not enough. Given these
| extreme events that led to this catastrophic flooding are
| increasingly common and that no action in climate change will
| change this in the short or even medium term, it's time to build
| dams. Lots of them.
|
| [1]: https://www.theguardian.com/global-development-
| professionals...
| _eht wrote:
| We need to airdrop more beavers, clearly.
| Melatonic wrote:
| This might actually not be a bad idea. That being said I
| think a lot of the environments would be too dry for beavers
| and not contain enough trees. Or conversely be too alpine.
|
| So basically we need genetically engineered super beavers
| that are adapted for high altitude mountaineering.
|
| On another note I find it hilarious and also cruel that
| beavers are apparently absolutely obsessed with stopping the
| sound of any running water. To the point that if one wanders
| near your home and can regularly hear water running inside of
| pipes it drives them crazy.
| andirk wrote:
| Using naturally skilled animals to pick up where we humans
| either fail or deny an issue is something we should
| seriously consider as a hedge at this point. If we can get
| extremely rich people even more rich by doing so, we may
| have a chance at it catching on.
| eldaisfish wrote:
| dams work well in regions with limited rainfall. The indian
| subcontinent receives most of its annual rainfall during the
| monsoon. Periods of 100 mm/hour of rainfall are not uncommon.
| Annual rainfall numbers in southern asia are often 1000 mm.
| North america's closest regions with that level of rainfall are
| all west of the rocky mountains.
|
| Dams are unlikely to help here and pose a serious risk if they
| break - which they can in a region prone to earthquakes.
| ageofwant wrote:
| Dams destroy ecosystems, reduce biodiversity and often just
| silt up. A related but far better idea is to encourage water
| retention on a far bigger scale by building johads or berms
| everywhere. See the Paani foundation's work in next door India.
| ouid wrote:
| its possible we didnt look at the same flood map or i'm looking
| at it wrong, but the way i read it it says that >5% of the
| country is flooded. Thats beyond the scope of dams to handle i
| believe.
| aaaaaasss wrote:
| R0b0t1 wrote:
| baybal2 wrote:
| Because rains been going on for so long this years. Heavy rains
| went for 2+ months so far across different parts of the country.
|
| Way longer that 1-2 weeks intense monsoon downpour.
| andyjohnson0 wrote:
| _" Pakistan is home to over 7,200 glaciers, more than anywhere
| outside the poles. Rising temperatures, linked to climate change,
| are likely making many of them melt faster and earlier, adding
| water to rivers and streams that are already swollen by
| rainfall."_
|
| https://www.vox.com/science-and-health/2022/8/30/23327341/pa...
| tuatoru wrote:
| > climate change ... [glaciers] melt faster and earlier
|
| Yes, this has been strongly predicted by climate models since
| forever. Mark Lynas' 2006 book _Six Degrees_ , which summarised
| climate change research up to about 2005, has a section on
| this.
|
| The prediction was that Pakistan will be wetter (i.e. have
| higher river flows) than historical averages through the 2020s
| because of glacial retreat.
|
| Sometime in the late 2030s or early 2040s, the glaciers will be
| effectively gone, and Pakistan will be without water, except
| during the monsoon (which may be more erratic - different
| models still say different things here). The rest of the year,
| the river beds will be dry.
|
| The time to start planning flood control and water retention
| structures was 20 years ago. Better late than never, though.
| nomel wrote:
| > Pakistan is home to over 7,200 glaciers, more than anywhere
| outside the poles
|
| It seems odd to give a measure of ice as the count of the
| pieces.
| booboofixer wrote:
| See 'List of longest glaciers on Earth in non-polar regions'
|
| https://en.m.wikipedia.org/wiki/List_of_glaciers
| throwaway09223 wrote:
| Kind of, right? But it also makes sense. We might talk about
| a highly populated country having a lot of cities -- even
| though cities are just somewhat loosely defined pieces of the
| population total.
| MichaelZuo wrote:
| I've never heard of anyone talk of the total number of
| cities in China, or India, or Indonesia, etc. Where do
| people talk like that?
| bmismyname wrote:
| 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 dies.
|
| People think about soil as just dirt, which it is not. Soil is
| effectively a living organism (or ecosystem of organisms).
| ok_dad wrote:
| Crazy to think we might actually kill the soil. Imagine a place
| like mars, because of the soil dies so will everything else.
| CommanderData wrote:
| 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?
| mountaintimefrm wrote:
| 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.
| peteradio wrote:
| 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.
| Panino wrote:
| 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, Saudi Arabia, Arizona and elsewhere). And I assume
| permaculture vastly increases water infiltration. Geoff
| Lawton has videos showing Zaytuna Farm happily surviving
| drought and flood alike.
|
| If farmers switched from conventional agriculture to some
| combination of regenerative agriculture and permaculture,
| most flooding would be prevented. Their own fields would
| _easily_ infiltrate rain, eliminating runoff that builds up
| into flooding.
|
| The article mentions that in addition to Pakistan getting
| double the normal amount of rain, increased glacier melt is
| filling the Indus river. I assume that in the theoretical
| situation of all farmers in Pakistan practicing regenerative
| ag or permaculture, that land on the Indus would flood. But
| not 1/3 of the country as we're seeing now, and the flooded
| areas would recover faster.
| alar44 wrote:
| Yeah just imagine if a billion people completely changed
| their way of life.
| IX-103 wrote:
| I'm not sure if you're being sarcastic or not. Climate
| change is going to require changes of at least that
| scale, whether we reduce emissions or not.
| zaroth wrote:
| Luckily for humanity that won't actually be necessary.
|
| In the next 20-30 years I suspect we'll just moderate
| total solar irradiance as-needed by injecting moon dust
| into L1.
|
| The only issue is if there are powerful countries that
| are actually benefiting from the warming and don't want
| to cool it down bit.
| lijogdfljk wrote:
| Imagine if they don't.
| peteradio wrote:
| 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, but would it have really have changed
| the image featured in this comment:
| https://news.ycombinator.com/item?id=32692060 ? Is the
| supposition that this water would find its way to some
| aquifer?
| carapace wrote:
| 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.
| CapitalistCartr wrote:
| Living in similar conditions in Florida, I know at about
| 4 inches per hour on a plain, you're screwed. It floods
| badly. And we have excellent drainage systems.
| Panino wrote:
| > Any link to read about this 0.5 - 30 inch/hr
| conversion?
|
| Read _From Dirt to Soil_ by Gabe Brown. He also mentions
| the first inch (2.5cm) infiltrates in 9 seconds! So his
| soil drinks up more water in 9 seconds than nearby farms
| do in an entire hour.
|
| > was this a carefully controlled experiment?
|
| NRCS water infiltration tests.
|
| https://www.nrcs.usda.gov
| asah wrote:
| naive q: does that still help if the aquifer gets
| saturated?
| nerdponx wrote:
| Is an aquifer ever likely to get saturated? I have no
| expertise in this area, but in the US at least the
| concern is always over aquifers being _depleted_ , not so
| fully saturated that they can't absorb more water. My
| understanding was that it takes very long time for water
| to actually get from ground level down into an aquifer.
| munificent wrote:
| This depends _entirely_ on where you live. Sure in the
| Southwest, there 's a big problem with drought. But along
| the Gulf Coast, the water table is astonishingly close to
| the surface. When my family put in an in-ground pool in
| Louisiana, they had to start filling the concrete pool
| with water even before finishing it because if they left
| it empty, the surrounding water table would push it up
| out of the ground like a floating boat.
| bombcar wrote:
| At _some_ point the ground cannot accept anymore water,
| no matter what.
|
| Proof: oceans exist.
|
| The key to the whole thing is if you can _slow it down_
| enough so that a sudden deluge over a day /week/month has
| time to slowly drain out.
|
| Getting water into an aquifer takes time depending on how
| the soil is, but eventually the aquifer would rise to the
| surface and you'd have a marsh. Or it would rise higher
| and you'd have a lake.
| hedora wrote:
| 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.
| mountaintimefrm wrote:
| > Water infiltration is measured by digging a small hole,
| filling it with water, and seeing how fast it drains.
|
| Informally yes, but the scientific way is to use a ring
| infiltrometer: https://www.fao.org/3/s8684e/s8684e0a.htm
| -- Basically instead of digging a hole, you pound a pipe
| into the ground and then fill the pipe with water.
|
| As for agricultural practices being able to change soil
| composition multiple feet down, trees and tap-rooted
| plants are very effective at placing large volumes of
| organic matter at depth. One example, Lacy Phacelia
| (Phacelia tanacetifolia) is an annual plant that produces
| a dense fibrous root system that reaches a depth of 4
| feet; in the fall the Phacelia plants die, and their
| roots decompose at depth, creating pathways for water
| infiltration while also increasing soil organic matter at
| depth. The same goes with other trees and shrubs. The
| farmer from the "It ain't much but it's honest work"
| meme, Dave Brandt, has some really enjoyable
| presentations on youtube about improving soil composition
| at depth.
| worik wrote:
| > . 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
| joshuajill wrote:
| Maybe even relatively simple but massive reforestation
| efforts could help mitigate climate change effects in the
| long run.
| worik wrote:
| 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.
| mountaintimefrm wrote:
| 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.
| loonster wrote:
| The more water that is retained on the property, the less
| that is available for entering streams.
| bergenty wrote:
| Lots of small water retaining walls and pits makes it so it
| doesn't run off and accumulate in some low central area.
| 11235813213455 wrote:
| permacultures are some super carbon sinks, anti-erosion
| systems, absorption systems and organic food producers, each
| one is just a grain of sand
| (https://en.wikipedia.org/wiki/Sorites_paradox), but many
| grains do the job along with lifestyle changes
| pvaldes wrote:
| I can't see how it could help having tons of plastic also
| floating in the river and expensive gravel filling the river
| bottom. The best way would still be to work with the monsoon,
| not against it.
|
| But maybe I'm not understanding the solution. Can you explain
| more the idea?
| sophacles wrote:
| Permaculture has nothing to do with tons of plastic nor
| gravel filling the river bottom.
|
| Permaculture is: the development of agricultural ecosystems
| intended to be sustainable and self-sufficient.
|
| I presume GP meant that by having more persistent vegetation
| in the area, that vegitation would do vegetation things and
| help with flood control.
| zackees wrote:
| aaaaaasss wrote:
| Nydhal wrote:
| climate change.
| raffraffraff wrote:
| "You have two life lines left: 50/50, and ask the audience"
|
| "I'm gonna go with A. Climate change "
| umvi wrote:
| Climate change has made us all incredibly intellectually lazy.
| Literally anything happens and we don't bother trying to
| understand why past "climate change".
|
| Natural disaster? Climate change. More or less
| insects/birds/rodents than usual? Climate change. More or less
| rain/snow/hail/heat/cold/storms/floods/droughts than usual?
| Climate change. Wildfire? Climate fire. Crypto currencies using
| record breaking amounts of electricity year over year? Climate
| change (impoverished countries ravaged by climate change turn
| to crypto currencies to escape their local inflated currency
| which further exacerbates climate change in a positive feedback
| loop - see what I mean?).
|
| In all of these cases climate change may indeed be a _piece_ of
| the puzzle, but due to intellectual laziness it has become the
| vast majority of the pie and we don 't bother to understand if
| there are other factors more influential than climate change.
| munk-a wrote:
| Climate change is happening and most of us live in a country
| (or next to a country, yay Canada!) where half the political
| body actively denies that it is happening and refuses to take
| action.
|
| As long as half of America continues to engage in such
| dangerous denialism there is no amount of drum beating that
| is excessive.
| marcosdumay wrote:
| Yeah, a drastic change on one of the most important aspects
| of the biosphere on the entire world is prone to lead to all
| kinds of changes.
|
| Usually people do go and verify, it's probably you that are
| not prone to looking. Almost always, it is global warming.
| This one time, we are not waiting for anybody to verify,
| because 50 years ago people were already predicting that
| global warming would almost certainly cause floods on the
| South littoral of Asia.
| butUhmErm wrote:
| I clicked back through the years available for my city on
| weatherspark.com
|
| Back in the 90s, never above 90-91 in Sept.
|
| In the last 10 years we started seeing 94-95 in Sept.
|
| Coincidentally air travel has doubled in that time period; from
| 2.25 billion people flying in 2010 to 4.56 billion in 2019. Of
| course that cratered since 2020.
|
| Thanks AirBnB and other apps that make burning fossil fuels a
| thoughtless, trivial thing?
| humanistbot wrote:
| > Thanks AirBnB and other apps that make burning fossil fuels a
| thoughtless, trivial thing?
|
| Your outrage is misdirected to something you probably
| personally relate to. Leisure travel is a minuscule component
| of the carbon in the atmosphere. Leisure travel is a fly
| hitching a ride on the beast that is global logistics, and
| AirBnb making leisure travel slightly cheaper and easier is a
| drop in the bucket for all leisure travel in general.
| butUhmErm wrote:
| "Outrage".
|
| Your qualification of my emotions is way off.
|
| 2.4% when talking tonnes may be a small percent relative to
| the "big picture" but it's not 0 tonnes, it has an impact,
| and production of machines to produce planes, production of
| more planes to keep up with rising demand are not included in
| that 2.4%. Leisure travel across the planet is not exactly a
| requirement for the survival of the species.
|
| It's still pushing our choices onto future humans.
|
| Since statistics are what matters to you; you're one of seven
| billion; your perspective is not that important.
|
| Probably best to avoid overly reductive rhetoric, the basis
| of which (statistical relevance) can be easily used against
| you. More co2 is released in service of the airline industry
| than just planes flying. The world is not made of singular
| statistical objects in a vacuum.
| andirk wrote:
| I doubt people going on a vacation a couple times per year is
| even a line item in the list of causes of burning fossil fuels.
| However, at the beginning of the pandemic, with fewer cargo
| vessels and even fewer personal vehicles burning fuel, we saw a
| measureable improvement to the environment within days.
| butUhmErm wrote:
| The planes in the air are not the only release of co2
| required to provide air travel.
|
| There's an industrial pipeline of machines to mine materials
| and machines to produce planes, all the travel to and from
| airports. The drink service carts don't just fall from the
| sky or grow on trees, they too have an entire industrial
| pipeline required for their production. Making travel easier
| puts more strain on planes necessitating more parts and net
| new planes sooner.
|
| The world is a miasma of statistics making up "the big
| picture".
| mring33621 wrote:
| Climate change is real and has changed the temporal distribution
| of rainfall, often increasing the interval between rainfalls,
| while also increasing the amount that falls, during rainy
| periods.
|
| Longer durations of 'no rain' cause the ground harden to a much
| less porous, concrete-like surface that cannot absorb the rain,
| when it does come, fast enough. So the water pools and flows,
| causing flood conditions.
| nerdponx wrote:
| The article also blames high amounts of glacial melt (to the
| point of bursting through glacial dams) sending a lot of extra
| water through waterways in a short amount of time.
| sremani wrote:
| With all due respect why are Glaciers melting in August.. or
| July or June. April and May are hot as hell in Indian
| Subcontinent.
|
| edit: glaciers melt in summer, I am surprised why they are
| melting in rainy season. No matter how you vote, just explain
| why this odd behavior.
| ajmurmann wrote:
| Why is that odd? Ice melts when it's warm.
| aeternum wrote:
| Except it has happened about every 12 years throughout history
|
| The ancients even created a name for it: La Nina.
| bmismyname wrote:
| Whatabout this thing that can happen at the same time as the
| climate changing due to human pollution?
| fiftyfifty wrote:
| Except this is our third La Nina year in a row, the first
| time that's ever happened:
|
| https://www.reuters.com/business/environment/wmo-
| forecasts-f...
| mokus wrote:
| That article only says it's the first this century.
| plantain wrote:
| As long as you define century as 2000-2100, and not
| 1922-2022...
| quietbritishjim wrote:
| That is how "this century" would typically be understood
| avgcorrection wrote:
| "This century" is fixed to start at 2000 until 2100, same
| as this decade is 2020-2029.
|
| "Last hundred years" for the former interpretation.
| Karellen wrote:
| Or 2001 until 2101, if you're being pedantic about the
| _N_ th century AD/CE.
|
| (Because there is no year 0 in the AD/CE calendar, so the
| first century in the calendar starts in year 1, the
| second in 101, etc...)
| plantain wrote:
| What?
|
| We had a triple dip in 1998, and before that 1976.
| soperj wrote:
| Also 1954-57.
| super_hacker wrote:
| handoflixue wrote:
| Huh, I didn't believe you at first but apparently there was
| indeed very severe flooding in 2010, and again in 1992.
|
| That said, back in 1992 this only affected 3 million people,
| and now it's 30 million. The population of the country only
| doubled over the same time span, so it seems like this year's
| flooding is easily five times worse than before
| piceas wrote:
| Land-use matters. I don't have a good link but there has
| been reporting on the topic.
|
| e.g. https://www.reuters.com/article/us-pakistan-
| environment-fore...
| pengaru wrote:
| > back in 1992 this only affected 3 million people, and now
| it's 30 million. The population of the country only doubled
| over the same time span, so it seems like this year's
| flooding is easily five times worse than before
|
| Or the distribution of people living in the flood plane
| drastically changed in that period. See my other comment @
| https://news.ycombinator.com/item?id=32653203
| hahaitsfunny wrote:
| MrRiddle wrote:
| Maybe the increase of population was mostly in affected
| areas, not 5 times worse.
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