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Offline Rafał

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #315 dnia: Wrzesień 26, 2017, 16:39 »
Autorzy wspomnianych badań wystosowali oświadczenie w reakcji na przesadzony/mylny odbiór wniosków w internecie:
https://www.theguardian.com/environment/2017/sep/21/when-media-sceptics-misrepresent-our-climate-research-we-must-speak-out
'zajawka - silne zainteresowanie, zamiłowanie' / pulsbiologii.pl

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #316 dnia: Wrzesień 27, 2017, 15:11 »
Searing summers becoming the new normal in Europe: study
September 27, 2017 by Marlowe Hood

Climate change has made the record-breaking temperatures that roasted parts of Europe this summer at least 10 times more likely, scientists reported Wednesday.

"We found clear evidence of human influence on this summer's record warmth, both in the overall summer temperatures and in the heatwave dubbed 'Lucifer'," said study co-author Geert Jan van Oldenborgh, a senior researcher at the Royal Netherlands Meteorological Institute.(...)

"If we do nothing to reduce our greenhouse gas emissions, the kind of extreme heat we saw this past summer will be the norm when my young son is a grown man," said co-author Friederike Otto, a scientist at the University of Oxford and deputy director of the Environmental Change Institute. (...)
https://phys.org/news/2017-09-searing-summers-europe.html

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #317 dnia: Wrzesień 27, 2017, 17:12 »
Wiatry zdmuchujące na krawędzie Antarktydzie głównie  śnieg zwalniają narastanie czapy polarnej.
Zjawisko to utrudnia prognozowanie wzrostów poziomu morza w wyniku procesów związanych z globalnym ociepleniem.

Antarctica: The wind sublimates snowflakes
September 25, 2017 Source: Ecole Polytechnique Fédérale de Lausanne

Researchers have observed and characterized a weather process that was not previously known to occur in Antarctica's coastal regions. It turns out that the katabatic winds that blow from the interior to the margins of the continent reduce the amount of precipitation (mainly snowfall) -- which is a key factor in the formation of the ice cap. By forming a very dry layer of air in the first kilometer or so of atmosphere, the winds turn the falling snowflakes during their fall directly from their solid state into water vapor in a process known as sublimation. The authors of this study used new data collected at the coast of Adélie Land over a yearlong period, together with simulations carried out using atmospheric models. They estimated that, across the continent, cumulative precipitation near the ground was 17% lower than its maximum level higher in altitude. Their measurements indicate that precipitation may be as much as 35% lower in the region around East Antarctica. The researchers believe that this phenomenon could be further aggravated by climate change. Their study has been published in Proceedings of the National Academy of Sciences. (...)

Data on the ice sheet's mass balance is essential for predicting how sea levels will rise or fall. Researchers generally expect global warming to result in higher levels of precipitation in Antarctica. But the impact of the katabatic winds on precipitation could challenge these forecasts and make them far more complicated. The team therefore plans to continue analyzing the continent. "We'd like to keep collecting data on coastal areas and look more closely at areas where the terrain is more complex. We also plan to use different types of atmospheric models for comparison purposes. Broadly speaking, we hope our work will help increase our understanding of how climate change will affect precipitation in Antarctica," explains Alexis Berne.

https://www.sciencedaily.com/releases/2017/09/170925151434.htm

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #318 dnia: Wrzesień 27, 2017, 17:33 »
Nowa góra lodowa wielkości 100 km kw. oderwała się od  lodowca Pine Island na Antarktydzie.


Polar View image of iceberg emerging from Pine Island Glacier taken on 26 September 2017

(...) Dr Larter continues: “If the ice shelf continues to thin and the ice front continues to retreat, its buttressing effect on PIG will diminish, which is likely to lead to further dynamic thinning and retreat of the glacier. PIG already makes the largest contribution to sea-level rise of any single Antarctic glacier and the fact that its bed increases in depth upstream for more than 200 km means there is the possibility of runway retreat that would result in an even bigger contribution to sea level.”

https://www.bas.ac.uk/media-post/large-iceberg-breaks-off-pine-island-glacier/
https://www.nasa.gov/multimedia/imagegallery/image_feature_2165.html

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #319 dnia: Wrzesień 29, 2017, 01:39 »
New measurements show widespread forest loss has reversed the role of tropics as a carbon sink
September 28, 2017

(...) Using this new capability, the researchers discovered that tropical regions are a net source of carbon to the atmosphere—about 425 teragrams of carbon annually, which is more than the emissions from all cars and trucks in the United States. Gross annual losses were about 862 teragrams of carbon and while gains were approximately 437 teragrams of carbon.

Losses and gains of carbon are not evenly distributed across the tropical belt, the report finds. On a continental scale, the majority of the loss (nearly 60 percent) occurred in Latin America, home to the Amazon—the world's largest remaining intact rainforest. Nearly 24 percent of the loss is attributable to Africa while the forests of Asia experienced the least losses—a little more than 16 percent of the tropical total. (...)
https://phys.org/news/2017-09-widespread-forest-loss-reversed-role.html

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #320 dnia: Październik 08, 2017, 19:34 »
In warmer climates, Greenlandic deltas have grown, new analysis of 75-year-old aerial photos confirms
October 4, 2017


The study investigates changes to the deltas since the 1940s and up until today. In the period between 1940 and 1980, the deltas did not change much, but as the climate became warmer, the deltas started to grow. The photo on the left shows a delta in West Greenland photographed in 1985 and on the right the same delta in 2010. It clearly shows how the delta has been extended by several kilometres over this 25-year period. Credit: Left: Danish Energy Agency. Right: Google Earth.

Deltas are important ecosystems, where freshwater meets the sea, and where people for centuries have been engaged in agriculture and fishing. Today, most of the deltas in the world are drowning because of increased human exploitation and a rise in the global sea level. In an article just published in Nature, a research team led by researchers at the University of Copenhagen has shown that deltas in Greenland, unlike most other deltas, are growing.

Deltas are important ecosystems, where freshwater meets the sea, and where people for centuries have been engaged in agriculture and fishing. Today, most of the deltas in the world are drowning because of increased human exploitation and a rise in the global sea level. In an article just published in Nature, a research team led by researchers at the University of Copenhagen has shown that deltas in Greenland, unlike most other deltas, are growing.

The team of researchers included Mette Bendixen and Lars L. Iversen from the University of Copenhagen, University of Colorado Boulder postdoctoral researcher Katy Barnhart—in the Cooperative Institute for Research in Environmental Sciences—and other Danish, American and Greenlandic scientists.

"We examined 121 deltas by looking at historical aerial photos taken by the American army during the Second World War" Bendixen said. "We compared these with modern satellite photos. In this way, we have been able to track changes in the Greenland deltas and see what has happened over the last 75 years."

The growing deltas are affecting the infrastructure in Greenland with major consequences for both fishing and tourism. The results from the study have altered our previous understanding of how the Arctic coast reacts to climate change.
"Our study shows how climate change affects environmental processes in the Arctic landscape. As a consequence of the warmer temperatures, more sediment is transported out to the coast. At the same time, the open-water period has been extended, and the material is therefore deposited in the deltas. And in this way, the deltas are growing," says Associate Professor Aart Kroon.

"Large parts of the Arctic coasts are being eroded, but in Greenland, we see the opposite happening. The study shows that climate change in the Arctic affects the coasts in a different way to what we have seen so far," said Bendixen.

https://phys.org/news/2017-10-warmer-climates-greenlandic-deltas-grown.html

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #321 dnia: Październik 09, 2017, 06:15 »
Soil holds potential to slow global warming, Stanford researchers find
OCTOBER 5, 2017  BY ROB JORDAN , Stanford Woods Institute for the Environment

The land under our feet and the plant matter it contains could offset a significant amount of carbon emissions if managed properly. More research is needed to unlock soil’s potential to mitigate global warming, improve crop yields and increase resilience to extreme weather.

If you want to do something about global warming, look under your feet. Managed well, soil’s ability to trap carbon dioxide is potentially much greater than previously estimated, according to Stanford researchers who claim the resource could “significantly” offset increasing global emissions. They call for a reversal of federal cutbacks to related research programs to learn more about this valuable resource. (...)

http://news.stanford.edu/2017/10/05/soil-holds-potential-slow-global-warming/

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #322 dnia: Październik 09, 2017, 06:57 »
Carbon Feedback from Forest Soils will Accelerate Global Warming, 26-Year Study Projects
OCTOBER 5, 2017 BY DIANA KENNEY , Marine Biological Laboratory

(...) Over the course of the experiment, Melillo’s team observed fluctuations in the rate of soil carbon emission from the heated plots, indicating cycles in the capacity of soil microbes to degrade organic matter and release carbon. Phase I (1991 to 2000) was a period of substantial soil carbon loss that was rapid at first, then slowed to near zero. In Phase II (2001-2007), there was no difference in carbon emissions between the warmed and the control plots. During that time, the soil microbial community in the warmed plots was undergoing reorganization that led to changes in the community’s structure and function. In Phase III (2008-2013), carbon release from heated plots again exceeded that from control plots. This coincided with a continued shift in the soil microbial community. Microbes that can degrade more recalcitrant soil organic matter, such as lignin, became more dominant, as shown by genomic and extracellular enzyme analyses. In Phase IV (2014 to current), carbon emissions from the heated plots have again dropped, suggesting that another reorganization of the soil microbial community could be underway. If the cyclical pattern continues, Phase IV will eventually transition to another phase of higher carbon loss from the heated plots.
Jerry Melillo, Distinguished Scientist and Director Emeritus of the Ecosystems Center at the Marine Biological Laboratory, Woods Hole, Mass.

Jerry Melillo, Distinguished Scientist and Director Emeritus of the MBL Ecosystems Center. Credit: Tom Kleindinst
“This work emphasizes the value of long-term ecological studies that are the hallmark of research at the MBL’s Ecosystems Center,” says David Mark Welch, MBL’s Director of Research. “These large field studies, combined with modeling and an increasingly sophisticated understanding of the role of microbial communities in ecosystem dynamics, provide new insight to the challenges posed by climate change.” (...)

http://www.mbl.edu/blog/carbon-feedback-from-forest-soils-will-accelerate-global-warming-26-year-study-projects/

”Błędne koło” emisji węgla z gleby przyspieszy globalne ocieplenie
13.10.2017

Ocieplające się wskutek zmian klimatu gleby będą uwalniać ogromne ilości węgla do atmosfery. Ten z kolei będzie przyspieszał globalne ocieplenie. Naukowcy ostrzegają przed ”błędnym kołem” emisji węgla, które odkryli podczas trwającego 26 lat eksperymentu.

Żaden inny eksperyment z tej dziedziny nie trwał tak długo. Przez 26 lat naukowcy badali, jak rosnące, globalne temperatury wpływają na gleby i przechowywany przez nie węgiel organiczny.
 
Odkryli, że gleby mogą uwalniać znacznie więcej węgla do atmosfery, niż dotychczas przypuszczano. Winowajcami są mikroby zawarte w glebie, które adaptując się do rosnących temperatur napędzają cykl naprzemiennych okresów uwalniania nadmiernych ilości węgla z podłoża do atmosfery i tych o minimalnej utracie węgla.
 
Jak ostrzegają badacze w publikacji na łamach najnowszego ”Science”, w ocieplającym się świecie taki samonapędzający - i prawdopodobnie niedający się kontrolować – cykliczny proces zachodzący między glebami a klimatem może znacznie przyspieszyć globalne ocieplenie.
 
Zespół pod kierownictwem Jerry’ego Melillo z Marine Biological Laboratory (MBL), niezależnego centrum badawczego w Woods Hole (USA), rozpoczął nowatorski eksperyment w 1991 roku na zalesionym terenie Harvard Forest w stanie Massachusetts.
 
Na wydzielonych poletkach naukowcy zakopali kable elektryczne i podgrzewali w ten sposób glebę o 5 st. C. powyżej temperatury panującej na poletkach kontrolnych.
 
Obserwacje z 26 lat wykazały, że ogrzewane poletka straciły w tym czasie 17 proc. węgla, który był przechowywany w materii organicznej w 60-centymetrowej warstwie gleby na powierzchni.
 
Proces uwalniania węgla z podłoża nie przebiegał jednak równomiernie. Po fazie znacznej utraty węgla z cieplejszej gleby nastąpiła faza, gdy emisje z podgrzewanych poletek były takie same, jak z poletek kontrolnych. Naukowcy tłumaczą ją adaptacją mikrobów w glebie do wyższej temperatury.
 
W kolejnym cyklu emisje węgla znów znacząco wzrosły, by ”wyciszyć się” na ostatnie trzy lata eksperymentu. I tym razem faza ta wynikała ze zmiany składu i aktywności mikrobów w glebie.
 
”Gleby na świecie zawierają około 3500 mld ton węgla organicznego. Jeśli znacząca ilość z tego trafi do atmosfery wskutek aktywności mikrobów w ocieplających się glebach, przyspieszy to proces globalnego ocieplenia” – mówi Melillo.
 
Przekonuje, że kiedy ten samonapędzający się proces już ruszy, nie będzie łatwo go zatrzymać. ”Tu nie ma wyłącznika, który można nacisnąć. (...) Jeśli mikroby w innych typach ziemskiego krajobrazu zareagują na ocieplenie klimatu podobnie, jak te w naszych leśnych glebach na umiarkowanej szerokości geograficznej, to mechanizm rozkręci się i nie będziemy w stanie powstrzymać tych mikrobów” – przekonuje naukowiec.
 
Szczególnym powodem do zmartwień są według niego ogromne zasoby węgla zamrożonego w arktycznych glebach. Jeśli ziemie te zaczną odmarzać, uwalniając węgiel do atmosfery i zaistnieje tam opisany w ”Science” mechanizm, stanie się on istotnym czynnikiem klimatycznym.
 
”Zmiana klimatu zacznie się sama napędzać w coraz bardziej ocieplającym się świecie” – podsumowuje Melillo.
 
Mimo publikacji wyników eksperymentu nie zakończono. Badacze MBL nadal kontynuują obserwacje w Harvard Forest. (PAP)
http://naukawpolsce.pap.pl/aktualnosci/news,460070,bledne-kolo-emisji-wegla-z-gleby-przyspieszy-globalne-ocieplenie.html
« Ostatnia zmiana: Październik 15, 2017, 23:57 wysłana przez Orionid »

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #323 dnia: Październik 10, 2017, 07:51 »
Droughts and wildfires: How global warming is drying up the North American monsoon
New insights into the droughts and wildfires of the southwestern US and northwestern Mexico
Date: October 9, 2017 , Source: Princeton University

Summary:
Previous researchers had concluded that global warming was simply delaying the North American monsoon, which brings summer rains to the southwestern US and northwestern Mexico. But a new, high-resolution climate model that corrects for persistent sea surface temperature (SST) biases now accurately reflects current rainfall conditions and demonstrates that the monsoon is not simply delayed, but that the region's total rainfall is facing a dramatic reduction.


This image shows the percent of July precipitation change.
Credit: Pascale et al./Princeton University/NOAA


Researchers have struggled to accurately model the changes to the abundant summer rains that sweep across the southwestern United States and northwestern Mexico, known to scientists as the "North American monsoon."


In a report published Oct. 9 in the journal Nature Climate Change, a team of Princeton and National Oceanic and Atmospheric Administration (NOAA) researchers have applied a key factor in improving climate models -- correcting for sea surface temperatures -- to the monsoon.

The report's authors include Salvatore Pascale, an associate research scholar in atmospheric and oceanic sciences (AOS); Tom Delworth, a lecturer in geosciences and AOS and research scientist at NOAA's Geophysical Fluid Dynamics Laboratory (GFDL); Sarah Kapnick, a 2004 Princeton alumna and former AOS postdoc who is currently a research physical scientist at GFDL; AOS associate research scholar Hiroyuki Murakami; and Gabriel Vecchi, a professor of geosciences and the Princeton Environmental Institute.

When they corrected for persistent sea surface temperature (SST) biases and used higher-resolution data for the regional geography, the researchers created a model that accurately reflects current rainfall conditions and suggests that future changes could have significant consequences for regional water resources and hazards.

"This study represents fundamental science relating to the physics of the North American monsoon, but feeds back onto weather to climate predictions and building resiliency for our water supply and responses to hazards," said Kapnick. "I am excited about this leap forward to improve our models and for the potential applications that they will provide in the future to society."

Their results highlight the possibility of a strong precipitation reduction in the northern edge of the monsoon in response to warming, with consequences for regional water resources, agriculture and ecosystems.

"Monsoon rains are critical for the southwest U.S. and northwest Mexico, yet the fate of the North American monsoon is quite uncertain," said Pascale, the lead author on the paper. "The future of the monsoon will have direct impacts on agriculture, on livelihoods."

Previous general circulation models have suggested that the monsoons were simply shifting later, with decreased rains through July but increased precipitation in September and October.

"The consensus had been that global warming was delaying the monsoon ... which is also what we found with the simulation if you didn't correct the SST biases," Pascale said. "Uncontrolled, the SST biases can considerably change the response. They can trick us, introducing artefacts that are not real."

Once those biases were corrected for, the researchers discovered that the monsoon is not simply delayed, but that the total precipitation is facing a dramatic reduction.

That has significant implications for regional policymakers, explained Kapnick. "Water infrastructure projects take years to a decade to plan and build and can last decades. They require knowledge of future climate ... to ensure water supply in dry years. We had known previously that other broadly used global models didn't have a proper North American monsoon. This study addresses this need and highlights what we need to do to improve models for the North American monsoon and understanding water in the southwest."

The new model also suggests that the region's famous thunderstorms may become less common, as the decreased rain is associated with increased stability in the lower-to-middle troposphere and weakened atmospheric convection.

"The North American monsoon is also related to extreme precipitation events that can cause flash floods and loss of life," Kapnick said. "Knowing when the monsoon will start and predicting when major events will happen can be used for early warnings and planning to avoid loss of life and property damage. This paper represents the first major step towards building better systems for predicting the monsoon rains."

The researchers chose to tackle the region in part because previous, coarser-resolution models had shown that this area would be drying out, a prediction that has been borne out in the droughts and wildfires of recent years. But most of those droughts are attributed to the change in winter storms, said Pascale.

"The storm track is projected to shift northward, so these regions might get less rain in winter, but it was very uncertain what happens to the monsoon, which is the other contributor to the rains of the region. We didn't know, and it's crucial to know," he said.

In their model, the researchers were able to tease out the impacts of one factor at a time, which allowed them to investigate and quantify the monsoon response to the doubling of atmospheric carbon dioxide, increased temperatures and other individual changes.

Pascale stressed the limits of this or any other climate model. "They need to be used with an understanding of their shortcomings and utilized to their expected potential but no further. They can give us quite reliable information about the large scale atmospheric circulation, but if you want to look at the regional, small-scale effects, you have to be very careful," he said. "Models are critical but they are not perfect, and small imperfections can lead to big misunderstandings."

He continued: "We are not saying, 'We are sure that this is what will be,' but we wanted to point out some mechanisms which are key, and have to be taken into account in future research on the North American monsoon. This is a difficult region, so future research will point out if we were right, and to what extent."

https://www.sciencedaily.com/releases/2017/10/171009123151.htm

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #324 dnia: Październik 13, 2017, 03:20 »
Z poniższej analizy wynika, że zamierzone działania przyjęte w paryskim porozumieniu klimatycznym przyjętego w 2016 są niestarczające do osiągnięcia wzrostu temperatury globalnej poniżej 2 stopni C do końca XXI wieku.

Beyond EPA's Clean Power decision: Climate action window could close as early as 2023
Oct 11, 2017 Contact Jim Lynch



ANN ARBOR—As the Trump administration repeals the U.S. Clean Power Plan, a new study from the University of Michigan underscores the urgency of reducing greenhouse gas emissions—from both environmental and economic perspectives.

For the U.S.'s most energy-hungry sectors—automotive and electricity—the study identifies timetables for action, after which the researchers say it will be too late to stave off a climate tipping point.

And the longer the nation waits, the more expensive it will be to move to cleaner technologies in those sectors—a finding that runs contrary to conventional economic thought because prices of solar, wind and battery technologies are rapidly falling, they say.

Steps outlined in the Clean Power Plan, as well as in the 2016 Paris climate accord, would not have been enough to meet the goal of keeping global temperature increase to 2 degrees Celsius by the end of this century, the study shows.

To achieve the 70-percent reduction target for carbon dioxide emissions used in the study, additional steps would be needed—and before 2023. The window for effective action could close that early.

"If we do not act to reduce greenhouse gas emissions forcefully prior to the 2020 election, costs ​to reduce emissions at a magnitude and timing consistent with averting dangerous human interference with the climate will skyrocket," said Steven Skerlos, U-M professor of mechanical engineering. "That will only make the inevitable shift to renewable energy less effective in maintaining a stable climate system throughout the lives of children already born."

Before Trump's reversal of both the domestic and international climate plans, the Intergovernmental Panel on Climate Change had recommended a 70-percent cut in carbon dioxide emissions from industrialized nations such as the U.S., where nearly half of emissions come from the electric and automotive sectors.

Using a custom, state-of-the-art model of these sectors, the researchers showed that the window for initiating additional climate action would close between 2023 and 2025 for the automotive sector and between 2023 and 2026 for the electric sector.

"That's true under even the most optimistic assumptions for clean technology advancements in vehicles and power plants," said study lead author Sarang Supekar, a mechanical engineering postdoctoral fellow at U-M.

Withdrawal from the accord and the EPA's plan to repeal the Clean Power Plan will only make the chances of achieving the goal more remote, the researchers say.

"In the absence of a government mandate, and if there is encouragement for coal to come back, then there's no way we can meet the target," Supekar said.

To arrive at their findings, Supekar and Skerlos calculated the future greenhouse gas contributions of the auto and power industries based on two approaches going forward—"business as usual" and "climate action." Their calculations relied on the lowest-cost technologies in each sector.

In the "business as usual" scenario, the auto industry followed its current rate of vehicle diversification—utilizing efficient internal combustion, electric and hybrid models, and the power sector utilized mostly natural gas and renewable plants. In the "climate action" scenario, those sectors relied on a greater percentage of cleaner automotive and power technologies to meet the IPCC climate goals.

"At some point, likely by 2023, you actually can't build the newer, cleaner power plants fast enough or sell enough fuel-efficient cars fast enough to be able to achieve the 70-percent target," Skerlos said.

Added Supekar, "The year-on-year emission reduction rate in such dramatic technology turnovers will exceed 5 percent after about 2020, which makes the 70-percent target infeasible for all practical purposes."

The analysis found no evidence to justify delaying climate action in the name of reducing technological costs, even under the most optimistic trajectories for improvement in fuels efficiencies, demand, and technology costs in the U.S. auto and electric sectors. In fact, the study found that waiting another four years to initiate measures on track with the 70 percent target would take the total cost for both sectors from about $38 billion a year to $65 billion a year.

"You could take this same model or a different model and arrive at different cost numbers using a your own set of assumptions for "business as usual" or interests rates, for instance," Supekar said. "But the point is, regardless of whether the cost of climate action today is $38 billion or $100 billion, this cost will rise sharply in three to four years from now."

The IPCC has determined that in order to keep Earth's average temperature from rising more than 2 degrees Celsius above pre-industrial times by the end of the century, global greenhouse gas emissions must be reduced between 40 percent and 70 percent by 2050. The U.S. is the largest cumulative emitter of greenhouse gases, and the electric and auto industries account for nearly half of the country's annual output. Fossil fuel combustion accounts for 95 percent of those industries' emissions.

The study, "Analysis of Costs and Time Frame for Reducing CO2 Emissions by 70% in the U.S. Auto and Energy Sectors by 2050," is published in Environmental Science and Technology. It was funded by the U-M Energy Institute and the National Science Foundation.

http://www.ns.umich.edu/new/releases/25157-beyond-epa-s-clean-power-decision-climate-action-window-could-close-as-early-as-2023

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Odp: Wzrost efektu cieplarnianego na Ziemi w ostatnich dekadach
« Odpowiedź #325 dnia: Wczoraj o 01:47 »
Naturalne metody pochłaniania CO2 ,  jak np. sadzenie więcej drzew może sprzyjać ograniczeniu średniego wzrostu globalnej temperatury.

New Study Finds Nature is Vital to Beating Climate Change
Washington, D.C., and London | October 16, 2017

Nature could cost-effectively deliver over a third of greenhouse gas emissions reductions required to prevent dangerous levels of global warming. This is equivalent to a complete stop to the burning of oil worldwide.

Better stewardship of the land could have a bigger role in fighting climate change than previously thought, according to the most comprehensive assessment to date of how greenhouse gas emissions can be reduced and stored in forests, farmland, grasslands and wetlands using natural climate solutions. (...)

THE BIGGEST NATURAL CLIMATE SOLUTION: MORE TREES

According to FAO, 3.9 billion hectares or 30.6% of total land area is forest. The researchers found that trees have the greatest potential to cost-effectively reduce carbon emissions. This is because they absorb carbon dioxide as they grow, removing it from the atmosphere. The results of the study indicate that the three largest options for increasing the number and size of trees (reforestation, avoiding forest loss, and better forestry practices) could cost-effectively remove 7 billion tonnes of carbon dioxide annually by 2030, equivalent to taking 1.5 billion gasoline-burning cars off the roads.

Restoring forests on formerly forested lands, and avoiding further loss of global forests, are the two largest opportunities. Success depends in large part on better forestry and agricultural practices, particularly those that reduce the amount of land used by livestock. Reducing the footprint of livestock would release vast areas across the globe for trees and can be achieved while safeguarding food security. Meanwhile, improved forestry practices across expanded and existing working forests can produce more wood fiber while storing more carbon, maintain biodiversity, and help clean our air and water. The researchers found that the top five countries where forests could reduce emissions the most are Brazil, Indonesia, China, Russia and India. (...)

https://www.nature.org/newsfeatures/pressreleases/new-study-finds-nature-is-vital-to-beating-climate-change.xml