|
Post by swamprat on Jul 24, 2019 19:06:21 GMT
Global scale of Earth’s recent warming is unique within the past 2000 years by Marric Stephens | 24 Jul 2019
Industrial revolution: before about 1850 warming and cooling events were distributed evenly around the globe. (Courtesy: Pixabay)
Warming experienced since the middle of the 20th century has been truly global with a geographic consistency not seen during any other period in the Common Era, which began 2000 years ago. This is the conclusion of an international team of researchers, who used an extensive range of climate proxies to map the regional and temporal scale of temperature changes over the last two millennia. The team showed that no climate trend prior to the current warming period has affected the entire planet simultaneously, and that historical temperature anomalies once assumed to have been worldwide affected different regions at different times.
The Roman Warm Period, the Dark Ages Cold Period and the Little Ice Age are some of the better known excursions from global mean temperatures that have occurred in the last two millennia. First identified from tree-ring data and other climate proxies in the northern mid-to-high latitudes, researchers initially expected to find the anomalies reflected in paleoclimate records across the globe. When evidence did come in from further afield, the data were noisy enough, and the temporal boundaries blurred enough, for it all to be accommodated within the prevailing narrative of global-scale change.
“There’s a dominant paradigm in which [paleoclimate researchers] think, and it’s the climate epochs paradigm, in which there were globally coherent periods of cold and warm,” says Nathan Steiger of Columbia University in the US. Steiger, with Raphael Neukom of the University of Bern in Switzerland, and colleagues at Spain’s University of Murcia, MathWorks in the US and the Bjerknes Center for Climate Research Norway, tested whether this paradigm holds for the Common Era.
Using a community-sourced database of climate records spanning all of the Earth’s continents and oceans, the team reconstructed annual temperatures over a global five-degree grid for the period AD 1–2000. The lack of any strong, universal influence on climate in the pre-industrial period was immediately obvious: virtually every single year up to 1850 saw at least a tenth of the Earth’s area experiencing above-average temperatures, while at least the same fraction experienced below-average temperatures.
Strictly regional phenomena
Familiar climate epochs like the Little Ice Age only emerged from the data when multidecadal average temperatures were taken, but even then, no single trend encompassed the whole of the planet at the same time. Instead, when the researchers plotted the timing of peak warming or cooling periods for each grid cell, they found that the climate events previously thought of as global epochs were strictly regional phenomena, consistent with natural climate variability.
“That stands in stark contrast to the contemporary warm period,” says Steiger, “where it really is very much globally coherent in a way that’s totally different from the global variability that happened prior to that over the past 2000 years”.
Steiger and colleagues describe their study in Nature.
In agreement with Steiger’s assessment, a second team (the PAGES 2k Consortium — which includes Neukom) reports in Nature Geoscience the result of a parallel analysis of the same data set. This group studied the rate at which global average temperature changed over multidecadal timescales and tried to identify the factors that drove such changes.
Volcanic eruptions
Prior to industrialization, they found that global temperature changes were influenced mainly by major volcanic eruptions, with greenhouse-gas forcing contributing a relatively minor signal. Solar output variability was not detectable in the multidecadal record.
Again, for the post-industrial period the picture was very different, with rates of warming since the mid-20th century exceeding anything seen in the preceding two millennia. “We see from the instrumental data and also from our reconstruction that, in the recent past, the warming rate clearly exceeds the natural warming rates that we calculate,” says Neukom.
Unusually warm or cold periods in the climate record are often seized upon by those who seek to deny the existence or downplay the consequences of anthropogenic climate change. After all, if temperatures varied so much before industrialization, why think that recent trends are anything extraordinary?
Although neither study investigated the specific drivers of recent warming, the fact that the current period stands apart in terms of both spatial coherence and warming rate still says something about this argument. As Neukom points out, many attribution studies have been performed over the last few decades, and the evidence all suggests that there are anthropogenic causes. “We do not explicitly test this; we can only show that natural causes are not sufficient to actually cause the spatial pattern and the warming rate that we observed.”
Marric Stephens is a freelance science writer based in Bristol, UK
physicsworld.com/a/global-scale-of-recent-warming-is-unique-within-the-past-2000-years/
|
|
|
Post by swamprat on Jul 25, 2019 15:14:45 GMT
Climate scientists drive stake through heart of skeptics' argument New research shows that the recent rise in global temperatures is unlike anything seen on Earth during the past 2,000 years.
A painting of a "frost fair" on River Thames in London in 1814 during a period known as the Little Ice Age when the river sometimes froze. 1814 was the last year a frost fair was held on the Thames. Guildhall Library and Art Gallery via Getty Images
July 24, 2019
By Jaclyn Jeffrey-Wilensky
Global warming skeptics sometimes say rising temperatures are just another naturally occurring shift in Earth’s climate, like the Medieval Warm Period of the years 800 to 1200 or the Little Ice Age, a period of cooling that spanned from roughly 1300 to 1850.
But a pair of studies published Wednesday provides stark evidence that the rise in global temperatures over the past 150 years has been far more rapid and widespread than any warming period in the past 2,000 years — a finding that undercuts claims that today’s global warming isn’t necessarily the result of human activity.
“The familiar maxim that the climate is always changing is certainly true,” Scott St. George, a physical geographer at the University of Minnesota in Minneapolis, said in a written commentary about the studies. “But even when we push our perspective to the earliest days of the Roman Empire, we cannot discern any event that is remotely equivalent — either in degree or extent — to the warming over the last few decades.”
Since the beginning of the 20th century, the global average temperature on Earth has risen by about 2 degrees Fahrenheit. A consensus of climate scientists pins the increase primarily on the burning of fossil fuels, which spews carbon dioxide and other heat-trapping greenhouse gases into the air. In the absence of concerted efforts to reduce greenhouse gas emissions, the United Nations says, the global average temperature could rise an additional 5.4 to 9 degrees Fahrenheit by 2100.
One of the studies, published in the journal Nature, shows that the Little Ice Age and other natural fluctuations affected only limited regions of the planet at a time, making modern warming the first and only planetwide warm period in the past two millennia. The other study, published in Nature Geoscience, shows that the rate of modern warming has far outpaced changes that occurred before the rise of the industrial era.
For the research, a team led by Raphael Neukom, a postdoctoral researcher at the University of Bern’s Institute of Geography in Switzerland, analyzed 2,000 years' worth of climate data. In the absence of direct temperature information — thermometer measurements were scarce before the middle of the 19th century — the scientists looked at data on old trees’ growth rings, layers of glacier ice and the remnants of corals, whose layers have different chemical compositions depending on the temperature of seawater.
The Nature study mapped the temperature fluctuations across the planet, finding, for example, that the Little Ice Age didn’t affect the whole world at once. Temperatures bottomed out in the Pacific Ocean around 1500, the scientists found; Europe and North America didn’t fully chill out for another two centuries.
The same pattern was observed for the higher temperatures seen during the Medieval Warm Period. The researchers found that less than half of the planet felt the heat at once.
The research indicates that during the current period of warming, more than 98 percent of the Earth’s surface has experienced record high temperatures. The finding shows just how dramatically today’s global rise in temperatures differs from previous periods of temperature change, the scientists said.
“What we show is that these periods aren’t globally coherent as previously thought,” said Nathan Steiger, a climate scientist at Columbia University in New York City and a co-author of the Nature study. The current period of warming “stands in stark contrast” to today’s warming, he added, calling it “a globally coherent warm period that is very different from what we see in the past.”
For the Nature Geoscience study, the researchers charted global temperature averages over time, and then compared the data to a set of climate simulations to figure out what might have driven the changes. Neukom and his colleagues found that the fastest warming in the last two millennia occurred during the second half of the 20th century.
The researchers also found that the main cause of temperature fluctuations changed over time. Prior to 1850, fluctuations were mainly linked to volcanic eruptions, which cooled the planet by spewing sun-blocking ash into the stratosphere; after 1850, greenhouse gas emissions took the wheel.
“It’s exciting to see studies like this that combine rigorous statistics with huge databases to make clear conclusions about past climate change,” said Gabriela Serrato Marks, a graduate student in paleo-climatology at the Massachusetts Institute of Technology in Cambridge, Massachusetts, who wasn't involved in the new research.
Serrato Marks said the records the researchers used could be incomplete, adding that subsequent research could benefit from more robust data. “Future studies will be strengthened even more with data from the Southern Hemisphere and more high-resolution data,” she said.
Jennifer Hertzberg, a paleo-climatologist at Old Dominion University in Norfolk, Virginia, who wasn’t involved in the research, called the study “very important” and praised its use of multiple statistical methods to reconstruct temperature change over time. She urged the public to take the results to heart.
“The global temperatures that we’re seeing now are higher than they have been in the last 2,000 years,” she said. “What we’re seeing now is uncharted territory. It’s time for everybody to wake up and make changes now.”
www.nbcnews.com/mach/science/climate-scientists-drive-stake-through-heart-skeptics-argument-ncna1033646?fbclid=IwAR1Vk_2g4B861FiJaKyo3Dt1Up5yl0cGiFyjDovwJGdCird7d8R1vZGVGhU
|
|
drwu
Full Member
Posts: 209
|
Post by drwu on Jul 25, 2019 17:22:55 GMT
It's all fake news...just ask Drumpf.
|
|
|
Post by nyx on Jul 25, 2019 18:46:59 GMT
Paris sets record 42.6 C or 108.7 F as a strong high pressure pushes North Africa heat into Europe.
It seems to me weather systems are not moving like they should because of the jet stream too far north.
|
|
|
Post by swamprat on Jul 27, 2019 17:04:18 GMT
After Scorching Europe, Heat Wave Is Poised to Melt Greenland By Mindy Weisberger, Senior Writer | July 26, 2019
Things are about to heat up in Greenland, which is already experiencing higher-than-average ice melt. Credit: Shutterstock
A heat wave that shattered records in Europe this week is on the move, and it could melt billions of tons of ice in Greenland.
Hot air that originated over Northern Africa recently brought blistering heat to Europe; yesterday (July 25), Paris sizzled at a staggering 108.7 degrees Fahrenheit (42.6 degrees Celsius), and temperature records were broken across the continent by up to 6 degrees F (3 degrees C), according to Accuweather.com.
Today (July 26), a representative of the World Meteorological Organization (WMO) announced that atmospheric flow would carry this scorching heat to Greenland, which lost over 170 billion tons (160 billion metric tons) of ice in July and 80 billion tons (72 billion metric tons) of ice in June from surface melting alone, Reuters reported.
When this warm air arrives in Greenland, it will likely cause "another major peak in melt area," said Twila Moon, a research scientist with the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado.
Intense melt during the summer months has been the norm rather than the exception in Greenland since 2006, NSIDC reported in 2013. More ice is lost every year, with the rate of melt accelerating rapidly, Moon told Live Science in an email. This could have serious implications worldwide by contributing to rising sea levels and further disrupting global climate, Joyce Msuya, the U.N. Environment's acting executive director, said in a statement in March.
"What happens in the Arctic does not stay in the Arctic," Msuya said. "More urgent climate action is needed to steer away from tipping points that could be even worse for our planet than we first thought."
Primed for melt
During the 1970s and the 1980s, Greenland lost an average of 50 billion tons (45 billion metric tons) of ice each year. From 2010 to 2018, that figure shot up to an average of 290 billion tons (263 billion metric tons) annually. This summer, the extent of the melt could surpass the record set in 2012. That year, about 97% of the ice sheet's surface thawed, NASA-JPL Caltech reported at the time.
"2012 was a year of particularly large ice loss. Unfortunately, an early melt event in Greenland in June may have primed some of the ice sheet surface for more melt," Moon said. The ice sheet is losing its surface snow; warming is also creating lakes and ice crystals on the sheet's surface, increasing the likelihood of further melting.
The good news is that even substantial ice loss from just one year probably won't create a tipping point for Greenland's ice sheet. The bad news is that significant ice loss over many years — with no years of ice gain — means that Greenland's accumulated ice is draining away at an unprecedented rate, Moon said.
"Maintaining this rapid ice loss over many years decreases the stability of Greenland and makes significant ice loss — and large associated sea level rise — more likely," she said.
However, it's not too late for people to mitigate the worst-case scenario for Greenland's ice by dialing back the greenhouse gas emissions that are fueling human-caused climate change, Moon said.
"Our collective actions will play a major role in determining how much and how quickly ice is lost from Greenland, and how severe the associated impacts will be," she said.
www.livescience.com/66041-heatwave-europe-greenland.html
|
|
|
Post by thelmadonna on Jul 27, 2019 18:08:58 GMT
www.bbc.co.uk/news/world-europe-49125391 Wildfires are ravaging the Arctic, with areas of northern Siberia, northern Scandinavia, Alaska and Greenland engulfed in flames.
Plumes of smoke from the fires can be seen from space.
Mark Parrington, a wildfires expert at the Copernicus Atmosphere Monitoring Service (Cams), described them as "unprecedented".
|
|
|
Post by swamprat on Jul 29, 2019 15:25:04 GMT
The emissions rebound effect: Trump's "Affordable Clean Energy" rule versus the Paris Agreement's "Clean Power Plan" versus "no plan"..... Affordable Clean Energy rule ‘worse than doing nothing’ 29 Jul 2019
by Kate Ravilious
You’d think that making coal-fired power stations more efficient would benefit the planet. But the policy currently proposed by the US Environmental Protection Agency will likely drive up greenhouse gas emissions, according to a study in Environmental Research Letters (ERL).
In June 2017 president Donald Trump announced that the US would cease all participation in the 2015 Paris Agreement on climate change mitigation. But this move didn’t completely negate the US obligation to regulate greenhouse gas emissions. Back in 2007 the US Supreme Court ruled that the Environmental Protection Agency has a legal obligation to regulate greenhouse gas emissions from existing power plants because it has been proven that greenhouse gas emissions endanger public health and welfare.
To meet these obligations the Environmental Protection Agency produced a Clean Power Plan, which established state-based emissions goals for fossil fired power plants. At the time it was finalized in 2015, it was estimated that the Clean Power Plan would decrease carbon dioxide emissions by 19% below business-as-usual level by 2030. However, Trump’s arrival in the White House forced a shake-up of many environmental plans, including the Clean Power Plan. Last August the Environmental Protection Agency released its proposed replacement for the Clean Power Plan: the Affordable Clean Energy rule.
Amelia Keyes from Resources for the Future, an independent non-profit research institution in Washington DC, and colleagues investigated the difference in impact that the Affordable Clean Energy rule will bring. Using the Environmental Protection Agency’s policy scenario modeling, along with projections of fuel generation and emissions datasets for all the different states, the team estimated carbon dioxide emissions up to the year 2030 under three scenarios: with the Clean Power Plan in place, with the Affordable Clean Energy rule in place and with no plan in place.
The researchers show that because the Affordable Clean Energy rule reduces the emissions intensity of individual power plants, it is likely to make coal-power a more popular choice. Hmmm..... Wonder if Big Coal is paying somebody a little stipend?! “It may also extend the lifetime of some coal plants and allow them to retire later, thus causing a greater number of coal plants to remain in operation,” says Keyes. This counterintuitive impact is known as the emissions rebound effect.
Currently the US produces around 27% of its electricity from coal. With the Affordable Clean Energy rule in place, Keyes and colleagues estimate that the US will produce 22.3% of its electricity from coal by 2030. With no policy in place that would fall to 21.4%, and with the Clean Power Plan in place coal power would make up 19.7% by 2030. In other words, the Affordable Clean Energy rule is not just less effective than the Clean Power Plan, but is actively worse than doing nothing, acting to slow the progress of weaning the US off fossil fuels.
It isn’t just carbon dioxide emissions that are a problem. Air quality will also take a hit, with emissions of sulphur dioxide projected to increase by up to 148% in 19 states and nitrogen oxide estimated to increase by up to 9% in 20 states plus DC by 2030 under the Affordable Clean Energy rule, compared to no policy.
“Our results demonstrate the importance of considering the emissions rebound effect…in evaluating the Affordable Clean Energy rule and similar policies targeting heat rate improvements,” the authors write in ERL.
physicsworld.com/a/affordable-clean-energy-rule-worse-than-doing-nothing/
|
|
|
Post by HAL on Jul 29, 2019 19:19:46 GMT
And Trump wants to reduce the regulation on vehicle emission.
It's obscene, isn't it.
HAL.
|
|
|
Post by swamprat on Jul 30, 2019 20:33:29 GMT
Yep.More Than 200 Reindeer Found Dead in Norway, Starved by Climate Change By Mindy Weisberger, Senior Writer | July 29, 2019
Researchers recently found more than 200 dead reindeer on the island of Svalbard in Norway; the animals starved to death due to climate change, which is disrupting their access to the plants that they typically eat.
Every year, ecologists with the Norwegian Polar Institute (NPI) survey reindeer populations in Svalbard, an archipelago of glaciers and frozen tundra that lies between Norway and the North Pole.
The findings from the scientists' 10-week investigation were grim: Reindeer population numbers were down, and the individual animals were much thinner than they should have been. And hundreds of reindeer carcasses showed signs of starvation, Norway's national news outlet, NRK, reported on July 27.
"It's scary to find so many dead animals," Åshild Ønvik Pedersen, an NPI terrestrial ecologist, told NRK. Reindeer in Svalbard are a subspecies, Rangifer tarandus platyrhynchus, and they are short-legged, with endearingly small, rounded heads. Males are slightly larger than females, measuring about 5 feet (1.6 meters) long and weighing up to 198 lbs. (90 kilograms), according to NPI.
Climate change is bringing warmer temperatures to Svalbard, which means more precipitation. And heavy rainfall in December is thought to be responsible for the unusually high number of reindeer deaths, the researchers wrote on May 28 on the NPI website.
After the December rain hit the ground, the precipitation froze, creating "tundra ice caps," a thick layer of ice that prevented reindeer from reaching vegetation in their usual winter grazing pastures. This forced the animals to dig pits in shoreline snow to find seaweed and kelp, which are less nutritious than the reindeer's usual fare.
NPI ecologists Hamish Burnett and Mads Forchhammer examine reindeer remains found in June. Credit: Siri Uldal/Norsk Polarinstitutt
The scientists also observed reindeer grazing on cliffs, which the animals rarely do during winters when food is more plentiful. Rocky, mountainous regions on Svalbard don't have much plant life, and this "mountain goat strategy" is risky for the reindeer, because the cliffs are very steep. But during lean years, about 50% of the reindeer climb to altitudes of nearly 1,000 feet (300 m) in a desperate search for food, the researchers reported.
With their pastures locked in ice, the reindeer also have to travel farther to find food. And when there is little to eat, the youngest and oldest animals are usually the first to die, Pedersen told NRK.
"Some of the mortality is natural because there were so many calves last year," she said. "But the large number we see now is due to heavy rainfall, which is due to global warming."
www.livescience.com/66047-200-dead-reindeer-norway.html
|
|
|
Post by thelmadonna on Jul 31, 2019 12:41:56 GMT
|
|
|
Post by nyx on Jul 31, 2019 15:15:40 GMT
Recent internet articles have talked about the rise in temperatures and heat as the enemy that is taking out our soldiers.
Heat deaths and heat injuries have soared in recent years, and it is causing havoc in the military.
|
|
|
Post by swamprat on Jul 31, 2019 18:43:28 GMT
Get me another beer... Met Office confirms highest temperature ever recorded in the UK The UK joined Germany, Belgium, Luxembourg, the Netherlands and six others in recording its highest-ever temperature during a continent-wide heatwave on 25 July. By Michael Le Page | 30 July 2019
As the world warms, yet another all-time national heat record has been set. The 38.7°C (101.7F)recorded in Cambridge Botanic Garden on 25 July during the recent European heatwave has now been confirmed to be the highest temperature ever recorded in the UK.
The UK’s Met Office checked the instrument and site before confirming the record, which is why it has taken a few days to confirm.
New all-time national records were also set on 25 July in Germany (42.6°C|108.7F), Belgium (41.8°C|107.2F), Luxembourg (40.8°C|105.4F) and the Netherlands (40.7°C|105.3F). Many more places across Europe also recorded the highest temperatures ever for those locations.
The heatwave was caused by a weather pattern that drew hot air from Africa northwards across a broad swath of Europe. Such patterns do occur from time to time, but because parts of North Africa are now 2°C hotter on average than in pre-industrial times, the plume of hot air was much hotter than it would have been without global warming.
“When the weather patterns, like we saw last week, bring air from this region to our shores it can bring a stronger signal of climate change with it too,” Peter Stott of the Met Office said in a statement.
More extreme heatwaves
The heatwave disrupted train travel as overhead wires on railways sagged and tracks buckled in the heat. Severe thunderstorms triggered by the heat and humidity also caused delays to flights.
The July heatwave in Europe came just a few weeks after a June heatwave set records. Many other parts of the world have also had record heat.
So far this year 11 countries have recorded their hottest ever temperatures, according to weather records compiler Maximiliano Herrera. None have recorded coldest ever temperatures.
None of the new heat records are likely to last long. The world has so far warmed around 1°C and is currently on track to warm 3 or 4°C by 2100. As the warming continues, heatwaves will continue to become ever more extreme.
www.newscientist.com/article/2211744-met-office-confirms-highest-temperature-ever-recorded-in-the-uk/ Amusement park mascot dies of heatstroke amid sweltering temps in Japan behind 10 other deaths By Travis Fedschun | July 31, 2019
A man dressed as a mascot at an amusement park in Japan is one of at least 11 people who have died in recent days as a result of a heat wave that's sent temperatures soaring across the country.
The 28-year-old part-time worker at the Hirakata Park in Hirakata was practicing for a dance performance around 7:30 p.m. Sunday on an outdoor stage while dressed as a fairy character, according to officials.
After dancing for about 20 minutes in the 35-pound outfit, the man lost consciousness and was rushed to the hospital, where he was pronounced dead, police told the Asahi Shimbun newspaper.
www.foxnews.com/world/amusement-park-mascot-dies-of-heatstroke-amid-sweltering-temperatures-in-japan-behind-10-other-deaths
|
|
|
Post by HAL on Aug 1, 2019 21:03:12 GMT
No problems here. Thank you for asking. We had a couple of very heavy downpours, but they were brief. The greatest potential damage appears to be to that dam in Derbyshire. If it gives way it will take the village below with it. But, looking at it, it seems that it is the wear surface of the overflow spillway that is damaged, not the main structure. So hopefully it will be ok. How did you do in Scotland ? HAL
|
|
|
Post by thelmadonna on Aug 1, 2019 21:43:20 GMT
How did you do in Scotland ?
It felt like a flash in the pan, a few hours of very heavy rain, a few really long rumbles of thunder, 3 flashes if lightning, no forks, wall lightning. My grass has grown about 5 ins.
The dam is a nightmare. A whole town has been evacuated.
|
|
|
Post by WingsofCrystal on Aug 1, 2019 23:23:36 GMT
How did you do in Scotland ? It felt like a flash in the pan, a few hours of very heavy rain, a few really long rumbles of thunder, 3 flashes if lightning, no forks, wall lightning. My grass has grown about 5 ins. The dam is a nightmare. A whole town has been evacuated. Sending up prayers for you all in Great Britain.
Crystal
|
|