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    TUHOKlimaticka zmena / Thank you so much for ruining my day
    TADEAS
    TADEAS --- ---
    TUHO: i lesy evropského mírného pásu byly v přírodním stavu pod silným pastevním tlakem,“

    ...

    Vědci zároveň upozorňují, že velkých kopytníků, i po zahrnutí domácích zvířat, není v krajině příliš, ale naopak i v porovnání s dobami ledovými, velmi málo

    ...

    S decimací velkých býložravců se pojí ještě jedna souvislost – nástup vlády ohně. Absence pastvy vede k akumulaci odumřelé rostlinné biomasy, ideálního paliva pro požáry. Jejich nástup lze poznat z přítomnosti ohořelých uhlíků v půdních profilech,“
    TUHO
    TUHO --- ---
    TUHO: Právě vyhubení velkých kopytníků podle vědců v současnosti stojí za úbytkem a ohrožením celé řady druhů vázaných na otevřenou krajinu nebo světlé lesy. V současnosti člověk tato prostředí v rámci ochrany přírody udržuje jen velmi pracně a nákladně. Přesto se mu nedaří obnovovat v krajině pestrou mozaiku, kterou dříve vytvářeli velcí kopytníci. „Pro udržení planetární biodiverzity zbývá jediné řešení: doplnit chybějící složky ekosystémů, zejména velké býložravce,“ zdůrazňuje Alena Sucháčková Bartoňová.
    V souvislosti s ochranou klimatu vědci proto varují před zjednodušenými recepty, které požadují výrazné zalesňování, případně redukce stád domácího skotu. Ta v mnoha oblastech nahrazují chybějící divoké velké kopytníky. Cestou je podle odborníků spíše méně intenzivní pastva.
    TUHO
    TUHO --- ---
    TUHO:
    Přežití stepní fauny a flóry v Evropě umožnil příchod pravěkých zemědělců a pastevců. Ti s pomocí stád domácího skotu a koní, kteří byli po staletí velmi podobní svým divokým předkům, zachovali v řadě oblastí krajinu otevřenou. Tam, kde se páslo méně, začaly krajinu sužovat požáry. „S decimací velkých býložravců se pojí ještě jedna souvislost – nástup vlády ohně. Absence pastvy vede k akumulaci odumřelé rostlinné biomasy, ideálního paliva pro požáry. Jejich nástup lze poznat z přítomnosti ohořelých uhlíků v půdních profilech,“ podotýká Alena Sucháčková Bartoňová.
    TUHO
    TUHO --- ---
    netyka se sicw uplne klimatickyxh zmen, ale je to okrajove k debatam o reforestaci

    Původní podoba krajiny v Evropě, včetně České republiky, byla mnohem otevřenější, než dnes. Její zarůstání a nástup lesů umožnil až člověk, který vybil stáda velkých býložravců, která do té doby bránila dřevinám v ovládnutí kontinentu. Čeští vědci na to upozorňují v rozsáhlém, dvojdílném článku, který publikoval časopis Vesmír.
    „S přítomností velkých savců souvisela diverzita rostlinstva a drobnějších živočichů. Krajina tehdejší mamutí stepi se v dnešním mírném pásu podobala krajině dnešního Altaje. Byla mozaikou stepí, sušších i vlhčích trávníků, rašelinišť a řídkých lesíků. Obývala ji směs druhů chladnomilných a kontinentálních až teplomilných, což lze dokázat nejen na fosilní megafauně, ale i na drobných savcích nebo broucích, jejichž těla se občas dochovala,“ vysvětluje Alena Sucháčková Bartoňová z Přírodovědecké fakulty Jihočeské univerzity a Entomologického ústavu Akademie věd České republiky.

    https://www.ceska-krajina.cz/...zornuji-vedci-nastup-lesu-umoznil-clovek-a-vybiti-velkych-bylozravcu
    TADEAS
    TADEAS --- ---
    Past evidence supports complete loss of Arctic sea ice by 2035
    https://phys.org/news/2020-08-evidence-loss-arctic-sea-ice

    A new study, published this week in the journal Nature Climate Change, supports predictions that the Arctic could be free of sea ice by 2035.

    ...

    Using the model to look at Arctic sea ice during the last interglacial, the team concludes that the impact of intense springtime sunshine created many melt ponds, which played a crucial role in sea-ice melt. A simulation of the future using the same model indicates that the Arctic may become sea ice-free by 2035.

    Joint lead author Dr. Maria Vittoria Guarino, Earth System Modeller at British Antarctic Survey (BAS), says, "High temperatures in the Arctic have puzzled scientists for decades. Unraveling this mystery was technically and scientifically challenging. For the first time, we can begin to see how the Arctic became sea ice-free during the last interglacial. The advances made in climate modeling means that we can create a more accurate simulation of the Earth's past climate, which, in turn gives us greater confidence in model predictions for the future."
    TADEAS
    TADEAS --- ---
    The value of seasonal energy storage technologies for the integration of wind and solar power
    https://pubs.rsc.org/en/content/articlelanding/2020/ee/d0ee00771d#!divAbstract

    This study considers the Western U.S. power system with 24% to 61% of variable renewable power sources on an annual energy basis (up to 83.5% of renewable energy including hydro, geothermal, and biomass power sources). Our results indicate that for the Western U.S. power system, pumped hydro and compressed air energy storage with 1 day of discharge duration are expected to be cost-competitive in the near future. In contrast, hydrogen storage with up to 1 week of discharge duration could be cost-effective in the near future if power and energy capacity capital costs are equal to or less than ∼US$1507 kW−1 and ∼US$1.8 kWh−1 by 2025, respectively. However, based on projected power and energy capacity capital costs for 2050, hydrogen storage with up to 2 weeks of discharge duration is expected to be cost-effective in future power systems. Moreover, storage systems with greater discharge duration could be cost-competitive in the near future if greater renewable penetration levels increase arbitrage or capacity value, significant energy capital cost reductions are achieved, or revenues from additional services and new markets—e.g., reliability and resiliency—are monetized.
    KEB
    KEB --- ---
    SHEFIK: hromadná nehoda převrácený kamion potřebuješ tam jít hasiče sanitku jeřáby to všechno rychle a po ucpané příjezdové cestě to moc nepůjde takže to nejspíš budeš muset vzít bokem atd.

    Neříkám že to není řešitelné, ale úplně snadné to nebude.
    TADEAS
    TADEAS --- ---
    SHEFIK
    SHEFIK --- ---
    KEB: jakou techniku/nehodu myslis? aut, nebo tech panelu? ta vyska je prece volitelna. pripadne teleskopicka, nebo odklopna, to bude resitelny jednoduse...
    KEB
    KEB --- ---
    SHEFIK: já nad tím přemýšlel taky, ale vždycky jsem narazil na to, jak chceš řešit nehodu, kam musí dojet technika. Ta demontáž by musela být rychlá jednoduchá bezpečná a levná
    TADEAS
    TADEAS --- ---
    2020 The appallingly bad neoclassical economics of climate change
    https://www.tandfonline.com/doi/full/10.1080/14747731.2020.1807856

    The appallingly bad neoclassical economics of climate change now published by @Globalizations. Open Access. Please promote as widely as possible

    My paper exposing the dreadful work on climate change done by William Nordhaus (and his band of like-simpleminded Neoclassical economists) has now been published by the journal Globalizations.


    TADEAS
    TADEAS --- ---
    Sky News | 2pm | 2 September 2020 | Extinction Rebellion UK
    http://www.youtube.com/watch?v=7ZQt8sNeNN8


    Channel 4 News | 1 September 2020 | Extinction Rebellion UK
    http://www.youtube.com/watch?v=KJJ_m0SBKHI
    TADEAS
    TADEAS --- ---
    Sea level rise from ice sheets track worst-case climate change scenario
    https://phys.org/news/2020-08-sea-ice-sheets-track-worst-case.amp

    Ice sheets in Greenland and Antarctica whose melting rates are rapidly increasing have raised the global sea level by 1.8cm since the 1990s, and are matching the Intergovernmental Panel on Climate Change's worst-case climate warming scenarios.

    According to a new study from the University of Leeds and the Danish Meteorological Institute, if these rates continue, the ice sheets are expected to raise sea levels by a further 17cm and expose an additional 16 million people to annual coastal flooding by the end of the century.

    Since the ice sheets were first monitored by satellite in the 1990s, melting from Antarctica has pushed global sea levels up by 7.2mm, while Greenland has contributed 10.6mm. And the latest measurements show that the world's oceans are now rising by 4mm each year.

    "Although we anticipated the ice sheets would lose increasing amounts of ice in response to the warming of the oceans and atmosphere, the rate at which they are melting has accelerated faster than we could have imagined," said Dr. Tom Slater, lead author of the study and climate researcher at the Centre for Polar Observation and Modelling at the University of Leeds.

    "The melting is overtaking the climate models we use to guide us, and we are in danger of being unprepared for the risks posed by sea level rise."
    SHEFIK
    SHEFIK --- ---
    trocha budoucnosti

    https://www.powermag.com/global-offshore-wind-capacity-slated-to-multiply-eight-fold-by-2030/

    Offshore wind capacity is slated to surge to more than 234 GW by 2030—a remarkable boost when compared to the current 29.1 GW that was installed worldwide at the end of 2019, the Global Wind Energy Council (GWEC) said in an August-released analysis of the sector.

    ...

    Offshore wind LCOE, notably, has tumbled in recent years, owing to installations of larger turbines. “When the bigger offshore turbine is released with a higher nameplate capacity, rotor diameter and tower height, the technical capacity factors are higher, which in turn increases the annual energy production (AEP),” the organization explained. “Although larger turbines per unit are more costly than smaller ones, it saves the CAPEX [capital expenditures] for foundations, cables and installation as well as the OPEX [operational expenditures] due to lower [numbers of] turbine units.”

    ...

    The group said that stored electricity can be electrolyzed into hydrogen to be used as feedstock to produce bulk chemicals like methanol or ammonia for industrial processes or combined with captured CO2 to make carbon-neutral liquid fuels such as crude, gasoline, diesel, and aviation fuels. It can also generate heat through heat pumps or electric boilers for houses and factories. Or it can be stored in underground formations like salt domes and fed back to the grid as needed. But while power-to-x has been shown to be technically feasible, the technology is “limited by the scale of projects, making it too expensive to be widely deployed at this stage.” However, the industry is primed to take the next step, “so it’s just a matter of ‘when,’ ” it said.
    XCHAOS
    XCHAOS --- ---
    SHEFIK: určitě ne první, vygoogli si Sea Bubbles. Hydrofoil efekt je úžasná věc, hlavně na stojatých vnittozemských vodách, pokud se podaří při rychlostech kolem 40 km/h je to úžasně efektivní mód dopravy... (lodím chybí obvykle právě rychlost...)
    SHEFIK
    SHEFIK --- ---
    nedavno jsem nad tim premejslel, kdyz neprosly panely na silnici, proc ne nad ni. snizi se tepelna zatez vozovky, hluk, svede se voda a snih bezpecne mimo, nemusi se na solar zabirat puda atd.

    Photovoltaics for highways – pv magazine International
    https://www.pv-magazine.com/2020/09/01/photovoltaics-for-highways/
    TADEAS
    TADEAS --- ---
    TADEAS:

    Up to half of world's water supply stolen annually, study finds | Murray-Darling Basin | The Guardian
    https://amp.theguardian.com/.../aug/27/up-to-half-of-worlds-water-supply-stolen-annually-study-finds
    SHEFIK
    SHEFIK --- ---
    jeste lepsi nez sme doufali

    Electric Cars Indirectly Emit Much Less Carbon Than Previously Reported
    https://insideevs.com/news/441944/electric-cars-emit-much-less-carbon/amp/

    In other words, electric cars would indirectly emit much less carbon and other gases than previous studies based on six main mistakes they made.

    ...

    1) The first one is an exaggeration in estimating the amount of carbon released in battery production. According to the Dutch researchers, the most accepted references to it (Buchal, Karl and Sinn, ADAC, ÖAMTC, and Joanneum Research) assume the process emits 175 kg of CO2 per kWh of battery. 

    All of them are based on a Romare and Dahllöf study from 2017. In 2019, that study was updated and lowered its estimate of carbon dioxide emitted in battery manufacturing from 175 kg/kWh to 87 kg/kWh. That alone reduced GHG emissions in half.

    ...

    2) The second mistake in establishing EVs’ carbon footprint is an underestimation of battery packs’ lives. The same studies we mentioned before believe EVs have an average lifespan of 150,000 km (93,200 mi).

    We have already spoken about million-mile batteries from SVolt and CATL that will soon be in production EVs. Even before that, the Dutch report estimates the current electric car life in 250,000 km. And it will improve quickly.

    ...

    3) The third mistake is assuming that the power grid will always be as dirty as when each EV hit the road for the first time. The truth is that it is getting cleaner. By coincidence, BloombergNEF published on September 1 that solar and wind represented 67 percent of all new power capacity added in the world in 2019. Fossil fuel sources of energy for electricity shrunk 25 percent. Remember that we are talking about a single year.

    ...

    4) What they say is that NEDC was a standard that allowed Dieselgate to happen and which is still the standard adopted by studies that criticize electric cars. WLTP would bring the hope of less biased tests.

    ...

    5) The fifth error they point out makes perfect sense. If people calculate how much carbon dioxide battery manufacturing emits, why not calculate how much is of it is generated when breaking oil down into its derivatives? 

    ...

    6) Finally, they argue that insisting on combustion engines is a mistake because they cannot improve much further. Even if we discover a revolutionary synthetic renewable fuel, they will not get much more energy efficient. A fair amount of it will be lost, while electric cars are efficient by nature. Any serious study on EV indirect emissions would have to consider that. 
    KEB
    KEB --- ---
    PAD: já si čím dál víc myslím, že Dukovany dopadnou, jak kanál Odra Dunaj cosi. Prodrbe se na tom mrtě milionů na studiích atd a pak se to shodí že stolu, že je to blbost.
    SHEFIK
    SHEFIK --- ---
    TADEAS: ja se na tohle tesim. nevim, ktery reseni nakonec zvitezi, ale predstava levny desalinace podel pobrezi afriky, nebo i jinde na svete ma potencial terraformingu :)
    Kliknutím sem můžete změnit nastavení reklam