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Five Climate Science Misconceptions – Debunked – The Wire Science

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A region in Assam affected by floods in 2015. Photo: Pradip Nemane/Wikimedia Commons


  • The climate of Earth has always changed, but the study of past climates shows us that the changes in the last 150 years have been exceptional and can’t be natural.
  • Taking the whole range of climate models suggests a doubling of carbon dioxide could warm the planet by 2º to 4.5º C, with an average of 3.1º C.
  • There is no scientific support for the continual denial of climate change.

The science of climate change is more than 150 years old and it is probably the most tested area of modern science. However the energy industry, political lobbyists and others have spent the last 30 years sowing doubt about the science where none really exists. The latest estimate is that the world’s five largest publicly-owned oil and gas companies spend about $200m each year on lobbying to control, delay or block binding climate-motivated policy.

This organised and orchestrated climate change science denial has contributed to the lack of progress in reducing global green house gas (GHG) emissions – to the point that we are facing a global climate emergency. And when climate change deniers use certain myths – at best fake news and at worse straight lies – to undermine the science of climate change, ordinary people can find it hard to see through the fog. Here are five commonly used myths and the real science that debunks them.

1. Climate change is just part of the natural cycle

The climate of Earth has always changed, but the study of palaeoclimatology, or past climates, shows us that the changes in the last 150 years – since the start of the industrial revolution – have been exceptional and cannot be natural. Modelling results suggest that future predicted warming could be unprecedented compared to the previous 5m years.

Global temperatures for the last 65m years and possible future global warming depending on the amount of greenhouse gases we emit. Illustration: Burke et al (2018)

The “natural changes” argument is supplemented with the story that Earth’s climate is just recovering from the cooler temperatures of the Little Ice Age (1300-1850AD) and that temperatures today are really the same as the Medieval Warm Period (900-1300 AD). The problem is that both the Little Ice Age and the Medieval Warming period were not global but regional changes in climate affecting north-west Europe, eastern America, Greenland and Iceland.

Also read: The Himalaya Are Becoming Giant Cash Cows

A study using 700 climate records showed that, over the last 2,000 years, the only time the climate all around the world changed at the same time and in the same direction has been in the last 150 years, when over 98% of the surface of the planet has warmed.

2. Changes are due to sunspots/galactic cosmic rays

Sunspots are storms on the Sun’s surface that come with intense magnetic activity and can be accompanied by solar flares. These sunspots do have the power to modify the climate on Earth. But scientists using sensors on satellites have been recording the amount of the Sun’s energy hitting Earth since 1978 and there has been no upward trend. So they cannot be the cause of the recent global warming.

A comparison of global surface temperature changes (red line) and the sun’s energy received by the Earth (yellow line) in watts (units of energy) per square metre since 1880. Illustration: NASA, CC BY

Galactic cosmic rays (GCRs) are high-energy radiation that originates outside our solar system and may even be from distant galaxies. It has been suggested that they may help to seed or “make” clouds. So reduced GCRs hitting the Earth would mean fewer clouds, which would reflect less sunlight back into space and so cause Earth to warm.

But there are two problems with this idea. First, the scientific evidence shows that GCRs are not very effective at seeding clouds. And second, over the last 50 years, the amount of GCRs have actually increased, hitting record levels in recent years. If this idea were correct, GCRs should be cooling Earth, which they aren’t.

3. CO₂ is a small part of the atmosphere – it can’t have a large heating affect

Eunice Newton Foote’s paper, Circumstances Affecting the Heat of the Sun’s Rays, American Journal of Science, 1857.

This is an attempt to play a classic common-sense card but is completely wrong. In 1856, American scientist Eunice Newton Foote conducted an experiment with an air pump, two glass cylinders and four thermometers. It showed that a cylinder containing carbon dioxide and placed in the sun trapped more heat and stayed warmer longer than a cylinder with normal air. Scientists have repeated these experiments in the laboratory and in the atmosphere, demonstrating again and again the greenhouse effect of carbon dioxide.

As for the “common sense” scale argument that a very small part of something can’t have much of an effect on it, it only takes 0.1 grams of cyanide to kill an adult, which is about 0.0001% of your body weight. Compare this with carbon dioxide, which currently makes up 0.04% of the atmosphere and is a strong greenhouse gas. Meanwhile, nitrogen makes up 78% of the atmosphere and yet is highly unreactive.

4. Scientists manipulate all data sets to show a warming trend

This is not true and a simplistic device used to attack the credibility of climate scientists. It would require a conspiracy covering thousands of scientists in more than a 100 countries to reach the scale required to do this.

Scientists do correct and validate data all the time. For example we have to correct historic temperature records as how they were measured has changed. Between 1856 and 1941, most sea temperatures were measured using seawater hoisted on deck in a bucket. Even this was not consistent as there was a shift from wooden to canvas buckets and from sailing ships to steamships, which altered the height of the ship’s deck – and these changes in turn altered the amount of cooling caused by evaporation as the bucket was hoisted onto deck. Since 1941, most measurements have been made at the ship’s engine water intakes, so there’s no cooling from evaporation to account for.

Also read: A Trip to the Top of the World, Where the Climate Crisis Is All Too Clear

We must also take account that many towns and cities have expanded and so that meteorological stations that were in rural areas are now in urban areas which are usually significantly warmer than the surrounding countryside.

If we didn’t make these changes to the original measurements, then Earth’s warming over the last 150 years would have appeared to be even greater than the change that has actually been observed, which is now about 1º C of global warming.

Reconstruction of global temperatures from 1880 to 2018 by five independent international groups of scientists. Illustration: NASA, CC BY

5. Climate models are unreliable and too sensitive to carbon dioxide

This is incorrect and misunderstands how models work. It is a way of downplaying the seriousness of future climate change. There is a huge range of climate models, from those aimed at specific mechanisms such as the understanding of clouds, to general circulation models (GCMs) that are used to predict the future climate of our planet.

There are over 20 major international centres where teams of some of smartest people in the world have built and run GCMs containing millions of lines of code representing the very latest understanding of the climate system. These models are continually tested against historic and palaeoclimate data as well as individual climate events such as large volcanic eruptions to make sure they reconstruct the climate, which they do extremely well.

Model reconstruction of global temperature since 1970, average of the models in black with model range in grey compared to observational temperature records from NASA, NOAA, HadCRUT, Cowtan and Way, and Berkeley Earth. Photo: Carbon Brief, CC BY

No single model should ever be considered correct as they represent a very complex global climate system. But having so many different models constructed and calibrated independently means that we can have confidence when the models agree.

Also read: India Must Stop Deforesting Its Mountains If It Wants to Fight Floods

Taking the whole range of climate models suggests a doubling of carbon dioxide could warm the planet by 2º 4 to 5º C, with an average of 3.1º C. All the models show a significant amount of warming when extra carbon dioxide is added to the atmosphere. The scale of the predicted warming has remained very similar over the last 30 years despite the huge increase in the complexity of the models, showing it is a robust outcome of the science.

By combining all our scientific knowledge of natural (solar, volcanic, aerosols and ozone) and human-made (greenhouse gases and land-use changes) factors warming and cooling the climate shows that 100% of the warming observed over the last 150 years is due to humans.

Natural and Human influences on global temperatures since 1850. Illustration: Carbon Brief, CC BY

There is no scientific support for the continual denial of climate change. The Intergovernmental Panel on Climate Change (IPCC), set up by the United Nations to openly and transparently summarise the science, provides six clear lines of evidence for climate change. As extreme weather becomes more and more common, people are realising that they do not need scientists to tell them the climate is changing – they are seeing and experiencing it first hand. The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Arctic could see more rain than snow in 30 years, study suggests – Eye on the Arctic

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In this Aug. 2005 file photo, an iceberg melts in Kulusuk, Greenland, near the Arctic Circle. A new report says the Arctic will be dominated by rain, rather than snow, sometime between 2050 and 2080. (John McConnico/AP Photo)

Increased rain detrimental to foraging Arctic mammals like caribou, reindeer, muskox

There could be more rainfall than snow in the Arctic in as little as 30 years because of the world’s changing climate, according to a new study that predicts the transition will happen decades earlier than previously anticipated.

The change is expected to happen sometime between 2050 and 2080, says research led by the University of Manitoba and published in the journal Nature Communications. Previously, the transition to a rain-dominated Arctic was expected to happen somewhere between 2070 and 2090.

Lead author Michelle McCrystall, a postdoctoral fellow at the university’s Centre for Earth Observation Science, said more than 50 per cent of precipitation in the Arctic falling as rain instead of snow will have “global implications” and a “very direct impact” on Indigenous people throughout the Arctic.

The biggest precipitation changes, she added, will happen during the fall. Predominant snowfall and snow precipitation is still expected in the winter months, even by the end of the century.

Some regions will make the transition earlier than others, she explained, based on their temperatures and proximity to the North Pole.

The study’s projections stem from an aggregation of data from around the world.

McCrystall said the 2050 to 2080 range in which the transition could happen reflects the variability of all the data that was used, but the average points to it happening, more specifically, around the year 2070.

Animal starvation

McCrystall said more rain in the Arctic would also lead to more rain-on-snow events — when rain falls onto an existing snowpack and freezes, forming ice layers either on the snow or within it — which would be “very damaging” for foraging mammals like reindeer, caribou and muskox.

Because of that ice, foraging animals will have a harder time reaching the grassland that lies beneath it.

“It can cause a huge starvation and die off in a lot of these populations,” she said.

Mark Serreze, a co-author of the study and the director of the National Snow and Ice Data Center in Boulder, Colo., said in a statement “the Arctic is changing so fast that Arctic wildlife might not be able to adapt.

“It’s not just a problem for the reindeer, caribou and muskox, but for the people of the North that depend on them as well.”

The mounted head of a muskox looks out over two Arctic exhibits at the Military Museums in Calgary in Feb. 2016. Foraging animals, like muskox, will have trouble reaching food sources below layers of ice in the snow caused by more frequent rain in the Arctic, said McCrystall. (Jeff McIntosh/The Canadian Press)

Kent Moore, a professor of atmospheric physics at the University of Toronto, who is outside of the research team, told CBC News that rain-on-snow events would also cause “incredible” stress on hairy animals like muskox.

“If it rains and then it freezes, then they get a kind of frozen ice on their body, and that can be very, very stressful for them. They can lose heat more rapidly.”

Transition likely to happen in our lifetime, study predicts

Moore said he’s not surprised the Arctic will see more rainfall in the future, but he is surprised when the researchers predict the transition to more rain than snow is going to happen.

“A couple of decades is pretty significant,” he said. “Animals have to adapt quick, but we also have to adapt quicker. And that’s always a challenge, that adaptation,” he said.

Walt Meier, a senior research scientist at the University of Colorado Boulder’s National Snow and Ice Data Center, who is also not one of the study’s authors, said a difference of a few decades means that this transition is more likely to happen in the lifespan of current generations.

“It becomes, for a lot of people, not something that maybe my children or grandchildren will see, but something I may very well live to see,” he said, adding that he, too, was not surprised by the new prediction.

Rising sea levels, thawing permafrost

Meier and McCrystall both said an increase in Arctic rainfall would contribute to rising sea levels, particularly because it will cause more glaciers along the coast of Greenland to fall into the water.

Rain fell on the summit of Greenland — a location where precipitation has previously always fallen as snow or ice — for the first time on record this year.

In this Aug. 2019 file photo, large icebergs float away as the sun rises near Kulusuk, Greenland. McCrystall said warmer temperatures and more rainfall in the Arctic means that more glaciers along the coast of Greenland will fall into the water. (Felipe Dana/The Associated Press)

The rain could also lead to permafrost thaw, said McCrystall.

“With more warming and more rainfall, that kind of percolates through the soil and will allow the soil to warm up,” she said. Permafrost stores carbon, she pointed out, and if it thaws “you’ll get a lot more greenhouse gases that will be emitted into the atmosphere.”

McCrystall said that increase in carbon creates a negative impact, because carbon emissions contribute to the further warming of the atmosphere.

“Changes that happen in the Arctic don’t really stay within the Arctic,” she said.

Though she doesn’t see her research as a call to action, McCrystall wants to see people putting more pressure on politicians to make tangible changes that will have big impacts in the fight against climate change.

The research team, which also included members from University College London, University of Colorado Boulder, University of Lapland and the University of Exeter, said that if the world is able to remain below 1.5 C of global warming, the transition to a rainfall-dominated precipitation might not happen in some Arctic regions.

But, if the world remains on its current trajectory, the transition is likely.

Related stories from around the North: 

CanadaOctober saw ‘extraordinary, record-setting heat’ in parts of Arctic Canada, CBC News

Finland: Cold weather perfect to pioneer electric aviation says Finnair, Yle News

GreenlandGreenland to join Paris climate agreement, Eye on the Arctic

Norway: Deep freeze in Arctic Europe sends power prices soaring, The Independent Barents Observer

Russia: Russia’s Arctic coast warmest since records started says weather service, The Independent Barents Observer

Sweden: Sweden aims to be ‘role model and bridge builder’ on climate change, Radio Sweden

United States: Author Q&A – Welp: Climate Change and Arctic Identities, Eye on the Arctic

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New dinosaur species from Chile had a unique slashing tail – Toronto Star

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Fossils found in Chile are from a strange-looking dog-sized dinosaur species that had a unique slashing tail weapon, scientists reported Wednesday.

Some dinosaurs had spiked tails they could use as stabbing weapons and others had tails with clubs. The new species, described in a study in the journal Nature, has something never seen before on any animal: seven pairs of “blades” laid out sideways like a slicing weapon used by ancient Aztec warriors, said lead author Alex Vargas.

“It’s a really unusual weapon,” said Vargas, a University of Chile paleontologist. “Books on prehistoric animals for kids need to update and put this weird tail in there. … It just looks crazy.”

The plant-eating critter had a combination of traits from different species that initially sent paleontologists down the wrong path. The back end, including its tail weapon, seemed similar to a stegosaurus, so the researchers named it stegouros elengassen.

After Vargas and his team examined the pieces of skull and did five different DNA analyses, they concluded it was only distantly related to the stegosaurus. Instead, it was a rare southern hemisphere member of the tank-like ankylosaur family of dinosaurs. (Though the stegouros name stuck and can be easily confused with the more well-known stegosaurus.)

Vargas called it “the lost family branch of the ankylosaur.“

The fossil is from about 72 million to 75 million years ago and appears to be an adult based on the way bones are fused, Vargas said. It was found with its front end flat on its belly and the back end angled down to a lower level, almost as if caught in quicksand, Vargas said.

From bird-like snout to tail tip, stegouros stretched about six feet (two meters) but would only come up to the thighs of humans, Vargas said.

The tail was probably for defense against large predators, which were also likely turned off by armor-like bones jutting out that made stegouros “chewy,” Vargas said.

Not only is this “a really bizarre tail,” but it is from far southern Chile, “a region that hasn’t yielded these types of animals before,” said Macalester College biologist Kristi Curry Rogers, who wasn’t part of the study.

“We’re just scratching the surface when it comes to a comprehensive understanding of dinosaur diversity,” Rogers said. “Stegourus reminds us that if we look in the right places at the right times, there is so much more still to discover.”

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Follow Seth Borenstein on Twitter at @borenbears.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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The Comet Leonard, the Christmas Star, and Other Things to See in December’s Night Sky – Lifehacker

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Photo: Ylenia Cancelli (Shutterstock)

There’s a lot going on in the night sky in December, from the spectacular Geminids meteor shower to Venus at its brightest. Here are some of December’s most impressive star-gazing highlights to mark on your calendar.

Venus will be at its brightest on Dec. 3

Venus is December’s planet of the month! An iconoclast and overachiever, Venus is the hottest planet in our solar system (sorry, Mercury), and the only one to spin clockwise. Venus will make its brightest appearance of 2021 (or “greatest illuminated extent,” according to astronomers) on Dec. 3. Look west right after sunset, and you should see the crescent Venus, although you might need binoculars to really check it out. With pressing business in other parts of the universe, Venus will disappear from Earth’s sky on Jan. 9.

Antarctic gets a total solar eclipse on Dec. 4

Our readers in Western Antarctica and sailors in the Ross Sea will be able to check out a total solar eclipse on Dec. 4, with sky-gazers in the rest of Antartica, South Africa, Tasmania, and the South Atlantic being able to see a partial eclipse. For the rest of us, the moon is new (i.e., not visible) so tides will be higher all over the world. Surf’s up, baby.

You can (probably) see Comet Leonard on Dec. 9

If you’ve been dying to check out a comet, may I suggest Comet Leonard? The mornings around Dec. 9 between 3:30 a.m. and dawn are prime viewing hours to see Comet C/2021 A1, also known as “Leonard.” According to Space.com, it will be “one-third of the way up the eastern sky, near the circle of stars that form the head of Serpens Caput (the Snake’s Head).” You might need binoculars to see it, and it might not be there at all (comets are hard to predict), but it’s worth a shot. What else are you gonna do during that time? Sleep?

The Geminids meteor shower peaks on Dec. 14

The Geminids meteor shower is the show-stopping celestial event of December 2021. It runs between Nov. 19 and Dec. 24, but its absolute peak is expected on Dec. 14. You should be able to see tons of meteors in the hours between sunset on Monday the 14th and sunrise on the 15th. At around 2 a.m., up to 120 meteors per minute might be visible. They’ll be all over the sky, but will appear to radiate from right above the stars of Castor and Pollux. These meteors would be even more spectacular without the moon messing things up with its reflected sunlight, but if you wait until it sets at around 3 a.m., more shooting stars should be visible.

You can spy on Crater Copernicus on Dec. 18

The moon crater Copernicus is visible with binoculars any time you can see the moon, but if you want to get really in-depth, check it out in a telescope on Dec. 18. On the night before the full moon, you’ll be able to see Copernicus’s terraced edges, its central peak, and its extensive ejecta blanket outside the crater’s rim. Copernicus is located slightly northwest of the center of the Moon’s Earth-facing hemisphere.

The full “Cold Moon” is coming on Dec. 19

Don’t miss December’s full cold moon on the 19th: Here’s everything you could ever want to know about it. 

Hunker down for the Winter Solstice on Dec. 21

In the Northern Hemisphere, Dec. 21 is the shortest day of the year. The sun is lowest at noon, and the darkness lasts longer than at any other day of the year. The Winter Solstice the best day for vampires who need to get a lot done. The exact moment of the solstice—when the sun reaches its most southernly point in the sky and Winter begins—happens at 15:59 Universal Time. Here’s how to translate Universal time to your local time.

See the little baby Ursids Meteor Shower peak on Dec. 22

This short meteor shower is caused by debris dropped by comet 8P/Tuttle, and is visible between Dec. 13 and 24, but its peak is expected in the early hours of the 22nd. After the moon sets at around midnight, you should be able to see five to ten meteors per hour in the sky. They could come from anywhere, but they will probably seem to radiate from above the Little Dipper.

See the Christmas Star on Dec. 25 (duh)

If you look out your window after midnight on Dec. 25, you should see Sirius, the brightest nighttime star, in the Southern sky. Sometimes called the “Dog Star,” Sirius is a twinkly blue and white ball of fire located a mere 8.6 light years from Earth. It is probably not the Star of Bethlehem that the three wise men from the East followed to Bethlehem—you can’t actually follow a star anywhere—but it’s still a cool star you can see on Christmas night (and other nights).

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