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    TUHOKlimaticka zmena / If the fracturing of our once stable climate doesn’t terrify you, then you don’t fully understand it
    TADEAS
    TADEAS --- ---
    COP26 Pledges will have Catastrophic Consequences, says Ex-NASA Climate Chief – Byline Times
    https://bylinetimes.com/2022/02/16/cop26-pledges-will-have-catastrophic-consequences-says-ex-nasa-climate-chief/

    The academic argues that, within the next six months, there will be a rise in the 12-month running-mean temperature due to the El Nino cycle, which will “be accelerated by Earth’s largest energy imbalance in the past half century”.

    By the second half of the 2020s, a further 0.1C will be added due to increased solar irradiance. The combined effect means that “there is now no chance whatever of keeping global warming below 1.5°C,” he says.

    Prof Hansen has also criticised COP26 President Alok Sharma who, after the summit in Glasgow, said “we can say with credibility that we have kept 1.5°C degrees within reach, but its pulse is weak”.

    ...

    Prof Hansen pointed to a range of evidence consistent with an imminent rapid sea level rise, including a brief time of rapid coral reef ‘backstepping’, and the vulnerability of the West Antarctic and later the East Antarctic ice sheets. “The eventual sea level rise for global temperatures expected by the middle of this century is at least 10 to 15 meters,” he concludes.

    Major cities at risk of being submerged in this way include New York City, Mumbai, Lagos, Shanghai, Miami, Dhaka and Tokyo.

    “The fact is that ice sheet disintegration is an exponential process with a characteristic time-scale (doubling or e-folding time that characterises exponential growth) of 10 to 20 years at maximum,” says Prof Hansen’s memo. “That statement is proven by the fact that sea level rise of several meters per century has occurred many times in Earth’s history.”

    The UN IPCC has under-estimated this danger due to simplistic ice sheet models that “are unable to reproduce rapid changes of sea level that occur repeatedly in the paleoclimate record,” Hansen states.

    Business as usual’ growth of greenhouse gases, he further argues, “likely will cause shut-down of the overturning North Atlantic and Southern Ocean overturning circulations by the middle of this century

    Both circulation systems play a critical role in regulating the stability of the Earth’s climate system. Recent models show that their shut-down could bring extreme cold to Europe and parts of North America, raise sea levels along the US East Coast, disrupt seasonal monsoons that provide water to much of the world, and further endanger the Amazon rainforest and Antarctic ice sheets.

    According to Prof Hansen, the most important effect may be reducing heat transfer from the southern to northern hemispheres, which would increase warming of the Southern Ocean at depth, accelerating Antarctic ice melt and driving sea level rise.
    TADEAS
    TADEAS --- ---
    TADEAS:

    If you read the papers and look at the data, we see that natural resources are deteriorating on every single continent. We’re far above sustainable levels. Even if we could avoid climate change, there is no possibility of sustaining 8 billion people at anything near the living standards we’ve come to expect. There have been some academic exercises to calculate how many people the earth could support. That’s really a silly sort of exercise, because it ignores most of the values and goals that we have for making human life on this planet worthwhile: equity, liberty, welfare, human health. These things are all intimately affected by overpopulation. I don’t know what a sustainable population level is now, but it’s probably much closer to a billion people, or fewer, if we aspire for them to have the kind of living standards and the political circumstances that we enjoy in the West.

    Depletion in the future is probably going to manifest most directly through what look like political forces. As countries like the United States and China become dependent on imports to sustain their living standards, which they are already with respect to oil, they will begin to implement political, military, and economic measures to gain control over those assets abroad. And that’s certainly going to bring us into conflict. Diverting resources off to the mechanisms of control will reduce the kind of growth that’s possible domestically. We can argue about how much technology will make new resources available to us, but the key thing to remember is that, generally speaking, technology is to be understood as a way of using fossil energy to secure something. And as our fossil energy resources start to decline, the ability of technology to make evermore abundant resources available is certainly going to go down.

    ...

    There are profound differences between what we did and the modeling which has been carried out in support of the IPCC. I respect that effort enormously. I know many of the people involved in trying to model long-term climate change. They are excellent scientists, and they’re doing good work. They have generated much useful new knowledge. But the nature of their analysis is just totally different from what we did. It wouldn’t be too much of an exaggeration to say that the IPCC model starts first with what is politically acceptable, and then tries to trace out its scientific consequences, whereas we looked at what was scientifically known, and then tried to trace out its political consequences.

    The IPCC model leaves many things exogenous. To use it you have to specify population growth assumptions, economic GDP level assumptions, and so forth. We worked very hard to make the important determinants of our model endogenous. It means that it evolves over time in response to changes that are occurring within the model. Making the important variables, like population, exogenous saves you a lot of criticism. You can give a bunch of different scenarios, and within that set, almost any politician will find something that they like.

    The IPCC scenario is just telling us about climate change, and does not get into other issues. We were trying to provide an overall framework. So, they’re both useful efforts, just totally different

    ...

    Energy availability, of course, is not only a matter of physical quantities, but also useful energy. The concept of energy return on investment (EROI) is extremely important, and probably well known to the people who monitor your website. We know that it’s trending down. Charlie Hall, in his pioneering work, has done the best job I’ve seen to calculate what EROI needs to be in order to sustain an economy as complex as ours. We have a ways to go, but it will be the decline of energy return on investment, which is the biggest problem.

    ...

    to get back down: to find ways to maneuver the system, in a peaceful, equitable, hopefully fairly liberal way, and bring our demands back down to levels that can be borne by the planet. That’s a totally different question than the one we addressed. It would require a totally different kind of model than the one we built, and a totally different set of books than the ones we wrote

    ...

    with these kinds of problems over time, the concern tends to go up, but the discretionary resources tend to go down. And it’s often the case that, by the time policymakers become sufficiently concerned about something to start wondering what to do, they no longer have sufficient discretionary resources to be very effective. And this is all compounded with what I call the time horizon vicious circle. Because we haven’t taken effective action in the past, crises are mounting. It’s in the nature of the political response that, when crisis comes, you focus more and more on the short term, and your time horizon shrinks. And because that leads you to do things which fundamentally don’t solve the problem, the crisis gets worse. So, as the crisis gets worse, the time horizon shrinks even more, bad decision making increases, and the crisis goes up even further. That’s where I see us now.

    ...

    If I were trying to start a new momentum for change, it would be on understanding the nature of human perception. Why is it that we tend to focus on the short term and the local, when in fact, the fundamental solutions to these problems are long-term and far away?

    ...

    There are two ways we change: socially and biologically. Fundamental genetic change in our species requires 3,000 or 4,000 years. It takes about that long before a constructive mutation can become fairly widespread. Social adaptation can, at least in theory, occur quicker, so the question here is: what are the prospects for our social system to change in ways that are more congruent with the reality? It’s high in theory. In practice, I’m not sure. The dominant issue we face is that the current system is serving the interests of many people very well. ... In the past, change happened rapidly under periods of crisis, not typically during periods of peace and success. As the crises grow we will see what change is available.
    TADEAS
    TADEAS --- ---
    Dennis Meadows on the 50th anniversary of the publication of The Limits to Growth - Resilience
    https://www.resilience.org/stories/2022-02-22/dennis-meadows-on-the-50th-anniversary-of-the-publication-of-the-limits-to-growth/
    TADEAS
    TADEAS --- ---
    XCHAOS: nebo male stroje na biomasu, aka kone a voli :)
    XCHAOS
    XCHAOS --- ---
    TADEAS: Proto mluvím o malých strojích. A ty se můžou pohybovat právě v blízkosti agrivoltaiky...

    Poslední chybějící článek jsou trochu lepší baterky... ale motivace je fakt nyní daleko větší, než třeba před 50 a více lety, kdy by se stejně akumulovala akorát energie z uhlí...
    SHEFIK
    SHEFIK --- ---
    TADEAS: ty panely nejsou v radach mezi plodinami, ale nad nimi, to bylo zase jadro meho sdeleni. Organickej strom ti takovyhle konstantni a pred zafixovany podminky nikdy nevytvori (vyska, prostor mezi, seskladani dle slunce v danym miste atd.)
    PER2
    PER2 --- ---
    A report released Wednesday by the UN Environment Programme suggests it's time we "learn to live with fire" and adapt to the uptick in the frequency and severity of wildfires that will inevitably put more lives and economies in harm's way
    TADEAS
    TADEAS --- ---
    PER2:

    centuries or decades / certain disaster or likely disaster / slow and steady or higher and faster TADEAS
    PER2
    PER2 --- ---
    lets fucking go!!!

    Greenland's ice is melting from the bottom up -- and far faster than previously thought, study shows

    Antarctic sea ice falls to lowest level since measurements began in 1979

    Climate change is intensifying Earth’s water cycle at twice the predicted rate, research shows
    TADEAS
    TADEAS --- ---
    TADEAS:

    Urban Talks: Občanská shromáždění - Marcin Gerwin (PL)
    https://vimeo.com/670608628
    GOJATLA
    GOJATLA --- ---
    TADEAS
    TADEAS --- ---
    SHEFIK: stromy jsou v radach, protoze prumyslovy zemedelstvi pouziva stroje a ty jezdej rovne ,) podobne jako panely jsou v radach, tam rozdil neni. v ramci planovani tech linii muzes davat stromy, nebo panely, z nekterejch hledisek to ma podobny vlastnosti, vc. zpusobu planovani v krajine. merit poznamky byl, ze by se ten impakt tedy mel srovnavat s pestovanim stejnych ploadin v ramci podobneho systemu, misto stinu panelu stiny stromu.

    v cr to urcite musi byt soucasti uzemniho planu, spousta obci ma solary mimo strechy zakazany.
    SHEFIK
    SHEFIK --- ---
    TADEAS: no nevim, co koukam na wiki a obrazky na googlu, asi to nebude zadnej slagr, ty stromy sou vetsinou v radach, nezakryvaj rovnomerne plodiny, v sussich oblastech budou brat zminenou vodu - kdyz nejde o les, spodni patro moc vlhkosti nedrzi, pac to vitr porad vysusuje.

    Co se tyka fotosyntezy, mas asi pravdu, nejspis u vetsiny plodin a hlavbe co se tyka zelenych casti rostlin, ale u dozravani plodu to bude prave to primy slunce par hodin denne, ktery napr. z vodnatyho rajcete udela sladky.. (plus za kratsi cas)
    TADEAS
    TADEAS --- ---
    XCHAOS: velky stroje (traktory, kombajny, i bagry, harvestory atp...) elektrifikovat je imho problem kvuli ty extremni narazovosti pouziti, kdy je nekdy potrebujes mit v provozu od rana do noci a pak zbytek roku stojej. tam to spis vidim na vodik, metan... coz muze bejt taky z lokalni anebo obnovitelny produkce.

    FV je dobra v tomhle uziti na chlazeni, kompresi sezonni produkce bioplynu .) ... ale v zime chladaky zase dohrivas :)
    TADEAS
    TADEAS --- ---
    SHEFIK: agrolesnictvi? pestujou se tak napr. obilniny, ale i zelenina. ... tu agrivoltaiku by bylo vhodny srovnavat s timhle, proteze se taky jedna o jinej nez ten nejmonokulturnejsi land-use (1 plodina), pricemz patro nizsich stromu zde nahrazujou panely, ktery delaj podobnou sluzbu.

    mam za to, ze fotosynteza jede lip v rozptylenym/difuznim slunecnim svetle, nez pod tou primou palbou zeshora. plus regulace vlhkosti, vetru. zanedbavam produktivitu stromovyho nebo kerovyho patra samotnyho. co se tyce xchaosem zminovanyho limitu vlahy a stormu - ano, nektera podnebi neumoznuji nebo jsou nevhodna, aby tam stromy byly... kere se pak stale daji pouzit a nektera ty 'sucha' agro'lesnictvi' s tim pracuji. vzdy jde o to dostat do systemu maximum pater - mnozit funkce.
    SHEFIK
    SHEFIK --- ---
    TADEAS: pod stromama se plodiny moc nepestujou imho. Jasne ze by to slo, ale asi bys nemaximalizoval moznej vynos. Takhle mas pod kontrolou denni svit i flexibilitu do budoucna pro ruzny plodiny... strom ti zaroven odcerpava vodu a negeneruje elektriku s potenciqlem elektromobility do budoucna, pac jak uvadej v clanku, cesta do.kesta je x-nasobne drazsi, jez nalup samotnej
    XCHAOS
    XCHAOS --- ---
    SHEFIK: tak zejména v tý Africe je zkrácení doby oslunění určitě důležité, může to zmírnit i vysychání půdy na přímém slunci, apod. Super, divil jsem se, proč v té Africe (navzdory nižší účinnosti ve vedru) s těma panelama nepohli už dávno.

    TADEAS: ano, ale tohle není tak jednoznačný, stromy vysouší půdu a odpařují vlhkost a třeba i v mírném pásu stačily 2 roky sucha, aby se některá stanoviště ukázala jako neschopná udržet takové množství stromů, které tam lidi vysadili. Když to přeženeš se stromy v savaně nebo ve stepi, tak jí můžeš klidně proměnit v poušt, protože zase takové množství lesa, které by ovlivnilo klima a přitáhlo srážky, není jednoduché dosáhnout a a když to děláš v oblasti, která dešt nepřitáhne ani když tam bude les, tak z toho máš průšvih.

    Takže zastínění solárními panely není tak nesmyslný industriálně (nebo spíš postindustriálně) - zemědělský kompromis, jak to vypadá. Nemluvě o tom, že abundance solární energie by mohla umožnit elektrifikaci drobné zemědělské mechanizace, což je ale vlastně přesně to, co potřebuješ místo dnešních traktorů a kombajnů.. třeba jak se uvažovalo, že by se nad poli posouvala mechanizace po jakýchsi kolejích, tak tohle se zrovna dá dobře spojiit i s tou fotovoltaikou...

    Ano, úplná krása to není, ale ty monokultury obilí obhospodařované kombajny jsou taky vlastně docela dystopické, když je srovnáš s tradiční kulturní krajinou. Je možné, že v boji s klimatickou změnou budeme možná muset ustoupit z některých estetických kritérií, ale ten výsledný ráz krajiny nemusí být až takový děs a i na ty stromy se tam určitě najde místo. Třeba proti obřím skleníkům agrivoltaika působí ještě docela v pohodě...
    TADEAS
    TADEAS --- ---
    SHEFIK: a na kterym control plot asi byla stejna mira zastineni stromama... (zadnym?)
    SHEFIK
    SHEFIK --- ---
    #agrivoltaics

    For example, cabbages grown under the 180, 345-watt solar panels have been a third bigger, and healthier, than those grown in control plots with the same amount of fertiliser and water.

    Kenya to use solar panels to boost crops by ‘harvesting the sun twice’ | Global development | The Guardian
    https://www.theguardian.com/global-development/2022/feb/22/kenya-to-use-solar-panels-to-boost-crops-by-harvesting-the-sun-twice
    TADEAS
    TADEAS --- ---
    TUHO: the economy of floodgates will be booming
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