adplus-dvertising
Connect with us

Science

Five Climate Science Misconceptions – Debunked – The Wire Science

Published

 on


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.

300x250x1

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.

Adblock test (Why?)

728x90x4

Source link

Continue Reading

Science

NASA to launch sounding rockets into moon's shadow during solar eclipse – Phys.org

Published

 on


This photo shows the three APEP sounding rockets and the support team after successful assembly. The team lead, Aroh Barjatya, is at the top center, standing next to the guardrails on the second floor. Credit: NASA/Berit Bland

NASA will launch three sounding rockets during the total solar eclipse on April 8, 2024, to study how Earth’s upper atmosphere is affected when sunlight momentarily dims over a portion of the planet.

The Atmospheric Perturbations around Eclipse Path (APEP) sounding rockets will launch from NASA’s Wallops Flight Facility in Virginia to study the disturbances in the created when the moon eclipses the sun. The sounding rockets had been previously launched and successfully recovered from White Sands Test Facility in New Mexico, during the October 2023 .

300x250x1

They have been refurbished with new instrumentation and will be relaunched in April 2024. The mission is led by Aroh Barjatya, a professor of engineering physics at Embry-Riddle Aeronautical University in Florida, where he directs the Space and Atmospheric Instrumentation Lab.

The sounding rockets will launch at three different times: 45 minutes before, during, and 45 minutes after the peak local eclipse. These intervals are important to collect data on how the sun’s sudden disappearance affects the ionosphere, creating disturbances that have the potential to interfere with our communications.

The ionosphere is a region of Earth’s atmosphere that is between 55 to 310 miles (90 to 500 kilometers) above the ground. “It’s an electrified region that reflects and refracts and also impacts as the signals pass through,” said Barjatya. “Understanding the ionosphere and developing models to help us predict disturbances is crucial to making sure our increasingly communication-dependent world operates smoothly.”

A sounding rocket is able to carry science instruments between 30 and 300 miles above Earth’s surface. These altitudes are typically too high for science balloons and too low for satellites to access safely, making sounding rockets the only platforms that can carry out direct measurements in these regions. Credit: NASA’s Goddard Space Flight Center

The ionosphere forms the boundary between Earth’s lower atmosphere—where we live and breathe—and the vacuum of space. It is made up of a sea of particles that become ionized, or electrically charged, from the sun’s energy or .

When night falls, the ionosphere thins out as previously ionized particles relax and recombine back into neutral particles. However, Earth’s terrestrial weather and space weather can impact these particles, making it a dynamic region and difficult to know what the ionosphere will be like at a given time.

It’s often difficult to study short-term changes in the ionosphere during an eclipse with satellites because they may not be at the right place or time to cross the eclipse path. Since the exact date and times of the are known, NASA can launch targeted sounding rockets to study the effects of the eclipse at the right time and at all altitudes of the ionosphere.

As the eclipse shadow races through the atmosphere, it creates a rapid, localized sunset that triggers large-scale atmospheric waves and small-scale disturbances or perturbations. These perturbations affect different radio communication frequencies. Gathering the data on these perturbations will help scientists validate and improve current models that help predict potential disturbances to our communications, especially high-frequency communication.

This conceptual animation is an example of what observers might expect to see during a total solar eclipse, like the one happening over the United States on April 8, 2024. Credit: NASA’s Scientific Visualization Studio

The APEP rockets are expected to reach a maximum altitude of 260 miles (420 kilometers). Each rocket will measure charged and neutral particle density and surrounding electric and magnetic fields. “Each rocket will eject four secondary instruments the size of a two-liter soda bottle that also measure the same data points, so it’s similar to results from fifteen rockets while only launching three,” explained Barjatya. Embry-Riddle built three secondary instruments on each rocket, and the fourth one was built at Dartmouth College in New Hampshire.

In addition to the rockets, several teams across the U.S. will also be taking measurements of the ionosphere by various means. A team of students from Embry-Riddle will deploy a series of high-altitude balloons. Co-investigators from the Massachusetts Institute of Technology’s Haystack Observatory in Massachusetts and the Air Force Research Laboratory in New Mexico will operate a variety of ground-based radars taking measurements.

Using this data, a team of scientists from Embry-Riddle and Johns Hopkins University Applied Physics Laboratory are refining existing models. Together, these various investigations will help provide the puzzle pieces needed to see the bigger picture of ionospheric dynamics.

The animation depicts the waves created by ionized particles during the 2017 total solar eclipse. Credit: MIT Haystack Observatory/Shun-rong Zhang. Zhang, S.-R., Erickson, P. J., Goncharenko, L. P., Coster, A. J., Rideout, W. & Vierinen, J. (2017). Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse. Geophysical Research Letters, 44(24), 12,067-12,073. https://doi.org/10.1002/2017GL076054

When the APEP- launched during the 2023 annular solar eclipse, scientists saw a sharp reduction in the density of charged particles as the annular eclipse shadow passed over the atmosphere.

“We saw the perturbations capable of affecting radio communications in the second and third rockets, but not during the first rocket that was before peak local eclipse,” said Barjatya. “We are super excited to relaunch them during the total eclipse to see if the perturbations start at the same altitude and if their magnitude and scale remain the same.”

The next total solar eclipse over the contiguous U.S. is not until 2044, so these experiments are a rare opportunity for scientists to collect crucial data.

Provided by
NASA

Citation:
NASA to launch sounding rockets into moon’s shadow during solar eclipse (2024, March 27)
retrieved 28 March 2024
from https://phys.org/news/2024-03-nasa-rockets-moon-shadow-solar.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

Adblock test (Why?)

728x90x4

Source link

Continue Reading

Science

Royal Sask. Museum research finds insect changes may have set stage for dinosaurs' extinction – CTV News Regina

Published

 on


Research by the Royal Saskatchewan Museum (RSM) shows that ecological changes were occurring in insects at least a million years before dinosaur extinction.

Papers published in the scientific journal, Current Biology, describe the first insect fossils found in amber from Saskatchewan and the unearthing of three new ant species from an amber deposit in North Carolina, according to a release from the province.

The amber deposit from in the Big Muddy Badlands of Saskatchewan, which was formed about 67 million years ago, preserved insects that lived in a swampy redwood forest about one million years before the extinction of dinosaurs.

300x250x1

“Fossils in the amber deposit seem to show that common Cretaceous insects may have been replaced on the landscape by their more modern relatives, particularly in groups such as ants, before the extinction event,” Elyssa Loewen, curatorial assistant, said.

The research team was led by Loewen and Dr. Ryan McKellar, the RSM’s curator of paleontology.

“These new fossil records are closer than anyone has gotten to sampling a diverse set of insects near the extinction event, and they help researchers fill in a 17-million-year gap in the fossil record of insects around that time,” Dr. McKellar said.

The three ant species discovered in North Carolina also belonged to extinct groups that didn’t survive past the Cretaceous period.

“When combined with the work in Saskatchewan, the two recent papers show that there was a dramatic change in ant diversity sometime between 77 and 67 million years ago,” Dr. McKellar said in the release.

“Our analyses of body shapes in the fossils suggests that the turnover was not related to major differences in ecology, but it may have been related to something like the size and complexity of ant colonies. More work is needed to confirm this.”

Adblock test (Why?)

728x90x4

Source link

Continue Reading

Science

Meteors, UFOs or something else? Dawson City, Yukon, residents puzzled by recent sightings in night sky – CBC.ca

Published

 on


Some residents in Dawson City, Yukon, say they’ve been seeing unusual things in the night sky lately — and it’s not the Northern Lights. 

But some might say it’s equally as fascinating.

Over the past few weeks, some residents have taken to social media to report seeing what they described as a fireball or meteor overhead. And last week, two residents said they both saw something similar.

300x250x1

Naomi Gladish lives in Henderson Corner, a subdivision approximately 20 kilometres from downtown Dawson City. She told CBC News she saw something while walking her dog Friday morning.

“I looked up and saw a bright star,” Gladish said. “Or what I thought was a star.” 

“Within a fraction of a second, I realized it was actually moving quickly. And then as I watched it, a second later it grew a long tail.”

Dawson City resident Naomi Gladish said she saw something similar to the fireball shown in this image from the American Meteor Society. (American Meteor Society)

Gladish said the unknown object started to change into a pale blue colour, like a gas flame. Then, a few seconds later, it appeared to burn out.

“I could see fire, or coal,” Gladish said. “Like red glowing bits, breaking off of it. And then that was it. I tried watching to see if I could see any dark chunks falling from that spot, or carrying on from that spot, but the sky was dark.”

A minute or two after Gladish saw what she thought was a meteor, she heard a boom in the distance.

“My dog and I both turned our head to that exact direction that I had just seen it,” she said.”I figured it was related.”

Two women walking through snowy mountain terrain.
Naomi Gladish hiking with her sister at Tombstone Park. (Submitted by Naomi Gladish)

Dawson resident Jeff Delisle reported seeing something similar at about the same time. He then took to social media to ask if anyone else had seen it. Two people responded saying they had. 

“It flew right above me,” Delisle wrote.

“Pretty cool looking…. What is it?”

Likely not a meteor, says astronomer

Christa Van Laerhoven, president of the Yukon Astronomical Society, came across Delisle’s post and got in touch. She asked about what he’d seen, such as how long it was in the sky and the colour.

Van Laerhoven told CBC News that based on descriptions from both Delisle and Gladish, she doesn’t believe it could have been a meteor.

She says a meteor would have been moving much faster, and the colouring would have appeared differently. 

“Meteors can be any colour but … as a rule, are a consistent colour. What these people were describing had different colours. So the head looked blue and then the tail was more of an orange,” van Laerhoven said.

“That’s just something that doesn’t happen with meteors.”

a meteor
This zoomed-in still from a dashcam video captured in 2020 by Louise Cooke from Mount Lorne, Yukon, shows what one space science expert said appears to be an unusually-bright meteor travelling across the sky. (Submitted by: Louise Cooke)

Van Laehoven believes there may be another explanation for the recent unusual sightings: space junk, falling to earth.

“Space junk, when it comes in … comes through the atmosphere and starts glowing that can be more irregular, because of the variety of materials that go into a spacecraft.”

Van Laerhoven also suggested it could a very fast plane, or someone playing with rockets.

Gladish, however, doesn’t think anyone in Dawson was playing with rockets on Friday morning.

“Unless they’re talking about someone in China, or like a distant land playing with very high, powerful rockets … then sure,” she said.

“This was not something that someone in Dawson was doing … This came from much, much higher and it was much, much different to anything that would be locally caused.”

Van Laerhoven also dismissed another possibility: alien visitors.

“If aliens were coming to Earth, we would know,” she said.

“Simply because it would take them so much effort to get here that it would be very hard to imagine them getting here and not doing something dramatic enough that we would actually know about it.”

Adblock test (Why?)

728x90x4

Source link

Continue Reading

Trending