A new study confirming that global climate change is man-made also found that the upper atmosphere is cooling dramatically due to rising CO2 levels. Scientists worry about the effect this cooling could have on orbiting satellites, the ozone layer and Earth's weather.
DoorFred Pierce • May 18, 2023
There is a paradox at the heart of our changing climate. As the blanket of air near the Earth's surface warms, most of the atmosphere above it cools dramatically. The same gases that heat the lowest miles of air cool the much larger tracts above that extend to the edge of space.
This paradox has long been predicted by climate modelers, but only recently has it been quantified in detail by satellite sensors. The new findings provide definitive confirmation of an important point, but raise other questions at the same time.
The good news for climate scientists is that the air cooling data does not confirm the accuracy of models that identify surface warming as anthropogenic. onenew studywas published this month in the journalPNASby veteran climate modeler Ben Santer of the Woods Hole Oceanographic Institution found that it increased the strength of the "signal" of the fingerprint of human climate change by fivefold, reducing the interfering "noise" of natural background variability. Sander says the finding is "indisputable."
But the new discoveries about the magnitude of the cooling in the air are raising new concerns among atmospheric physicists — about the safety of orbiting satellites, the fate of the ozone layer and the possibility of these rapid changes in the sky. and unexpected turmoil in our land. again below.
Increases in CO2 are now "manifested throughout the observable atmosphere", says one physicist.
Until recently, scientists called the outermost zones of the upper atmosphere the "agnosphere" because they knew so little about it. So now that they know more, what are we learning that should reassure or worry us?
Earth's atmosphere has a number of layers. The region we know best, because that's where our weather happens, is the troposphere. This dense blanket of air, five to nine miles thick, contains 80 percent of the mass of the atmosphere, but only a small fraction of its volume. Above there are large open spaces with less and less dense air. The stratosphere, which ends about 30 miles up, is followed by the mesosphere, which extends up to 50 miles, and then the thermosphere, which extends over 400 miles.
Below, these distant bands look like a calm and pristine blue sky. But they are actually buffeted by strong winds and huge tides of rising and sinking air that occasionally invade our troposphere. And the worry is that this already dynamic environment could change again as it is infiltrated by CO2 and other man-made chemicals that mess with the temperature, density and chemistry of the air in the air.
Climate change is almost always considered in terms of the lower regions of the atmosphere. But physicists are now warning that we need to reconsider that hypothesis. Increases in CO2 are now "manifested throughout the observable atmosphere".says Martin Mlinjak, an atmospheric physicist at NASA's Langley Research Center in Hampton, Virginia. They bring about "drastic changes [that] scientists are just beginning to understand." These changes in the wild blue far above our heads could feed back to change our world below.
The story of atmospheric temperature change at all levels is largely the story of CO2. We know very well that our emissions of more than 40 billion tons of gas per year are warming the troposphere. This is because the gas absorbs and re-emits solar radiation, heating other molecules in the dense air and raising the temperature overall.
But not all the gas stays in the troposphere. It also spreads upward throughout the atmosphere. We now know that the rate of increase of concentration at the top of the atmosphere is the same as at the bottom. But the effect on the temperature in the air is very different. In the thinner air in the air, most of the heat re-emitted by CO2 does not collide with other molecules. He escapes into space. Combined with greater heat retention at lower levels, the result is rapid cooling of the surrounding atmosphere.
The cooling of the upper air also causes contraction, which worries NASA. The sky is falling - literally.
Satellite data recently revealed that between 2002 and 2019, the mesosphere and lower thermosphere cooled by 3.1 degrees F (1.7 degrees Celsius). Mlynczakcalculatesthat a doubling of CO2 levels later this century will likely lead to a cooling in these zones of about 13.5 degrees F (7.5 degrees C), which is two to three times faster than the average warming recorded at ground level which is expected.
Early climate modelers predicted in the 1960s that this combination of tropospheric warming and strong cooling higher up was the likely effect of rising atmospheric CO2. But recent detailed confirmation from satellite measurements greatly increases our confidence in CO2's effect on atmospheric temperatures, says Santer, who has modeled climate change for 30 years.
This month, he used new data on cooling in the middle and upper stratosphere to recalculate the strength of the statistical "signal" of the human fingerprint on climate change. HeI found itthat it was greatly enhanced, particularly because of the added benefit of lower ambient noise in the upper atmosphere than natural temperature variability. Santer found that the signal-to-noise ratio for human influence increased fivefold, providing evidence of human effects on the thermal structure of Earth's atmosphere." "We are fundamentally changing that thermal structure," he says. "These results are very concerning."
Much of the research analyzing changes in the sky has been done by scientists employed by NASA. The space agency has the satellites to measure what's going on, but it also has a particular interest in the security implications of the satellites themselves.
This importance arises because the cooling of the upper air also causes it to contract. The sky is falling - literally.
The depth of the stratosphere has decreased by about 1 percent, or 1,300 feet, since 1980, according toanalysisfrom NASA data by Petr Pisoft, an atmospheric physicist at Charles University in Prague. Above the stratosphere, Mlynczak found that the mesosphere and lower thermosphere shrank by nearly 4,400 feet between 2002 and 2019. Part of that shrinkage was due to a short-term drop in solar activity that has since ended, but 350 feet of it was due to cooling caused by the extra CO2calculates.
This contraction means that the upper atmosphere becomes less dense, which in turn reduces drag on satellites and other low-orbiting objects — by about a third by 2070,calculatesIngrid Cnossen, researcher at the British Antarctic Survey.
On the face of it, this is good news for satellite operators. Their payloads will have to remain operational longer before falling back to Earth. But the problem is the other objects that share these heights. The growing amount of space junk -- any kind of equipment left in orbit -- also lingers longer, increasing the risk of collisions with currently operating satellites.
In 2020, the Arctic experienced its first complete ozone hole, losing more than half of its ozone layer in some places.
More than 5,000 active and inactive satellites, including the International Space Station, orbit at these altitudes, accompanied by more than 30,000 known pieces of debris larger than four inches in diameter. Collision risks, Cnossen says, will continue to rise as cooling and contraction accelerate.
That might be bad for the space agency's business, but how will changes in the sky affect our world below?
A major concern is the already fragile state of the ozone layer in the lower stratosphere, which protects us from harmful solar radiation that causes skin cancer. For much of the 20smcentury, the ozone layer has been depleted by industrial emissions of ozone-depleting chemicals such as chlorofluorocarbons (CFCs). Ozone holes formed around Antarctica every spring.
The 1987 Montreal Protocol aimed to close the annual gaps by eliminating these emissions. But it's now clear that another factor is undermining that effort: stratospheric cooling.
Ozone depletion works excessively in polar stratospheric clouds, which form only at very low temperatures, especially over polar regions in winter. But the cooler stratosphere has led to more occasions for such clouds to form. While the ozone layer over Antarctica is slowly reforming as CFCs disappear, the Arctic appears to be different, says Peter von der Gathen of the Alfred Wegener Institute for Polar and Marine Research in Potsdam, Germany. In the Arctic, cooling is exacerbating ozone loss. Von der Gathen says the reason for this difference is not clear.
In the spring of 2020, the Arctic experienced its first complete ozone hole with the loss of more than half of the ozone layer in some places, which Von der Gathen attributes to rising CO2 concentrations. It could be the first of many. In a recentpaperinContact with nature, warned that continued cooling means that current expectations that the ozone layer should fully heal by mid-century are almost certainly overly optimistic. As for current trends, he said, "conditions favorable for a large seasonal loss of ozone in the Arctic column may persist or even worsen through the end of this century ... much longer than is generally believed."
This is all the more concerning because, while the areas beneath the previous Antarctic holes were largely free of humans, the areas beneath the future Arctic ozone holes may be some of the most densely populated in the world, including the central and western Europe. If we thought that the thinning of the ozone layer was 20mconcerns of the century, we may need to rethink that.
Chemistry isn't the only problem. Atmospheric physicists are also increasingly concerned that the cooling may alter the upward movement of air in ways that affect ground-level weather and climate. One of the most turbulent of these phenomena is known assudden warming of the stratosphere. Westerly winds in the stratosphere periodically reverse, resulting in large temperature swings where parts of the stratosphere can warm up to 90 degrees F (50 degrees Celsius) in a few days.
This is usually accompanied by a rapid sinking of air that pushes the Atlantic jet stream into the upper troposphere. The jet stream, which powers large-scale weather systems across the northern hemisphere, is beginning to oscillate. This disturbance can cause a variety of extreme weather events, from sustained heavy rainfall to summer droughts and "blocking highs" that can bring weeks of bitterly cold winter weather from eastern North America to Europe and parts of Asia.
These are already known. For the past 20 years, meteorologists have incorporated such stratospheric influences into their models. This has greatly improved the accuracy of their long-term forecasts,according to the Weather Service, a UK government forecasting service.
"If we don't get our models right about what's going on up there, we might be wrong down there."
The question now is how additional CO2 and overall stratospheric cooling will affect the frequency and intensity of this sudden warming. Mark Baldwin, a climate scientist at the University of Exeter in England who has studied the phenomenon, says most models agree that the sudden warming of the stratosphere is indeed sensitive to more CO2. But while some models predict many more sudden warming events, others suggest fewer. Knowing more, Baldwin says, would "lead to greater confidence in both long-term weather forecasts and climate change predictions."
It's becoming increasingly clear that, as Gary Thomas, an atmospheric physicist at the University of Colorado Boulder, puts it, "If we don't get our models right about what's going on up there, we might be wrong down there." But improving models of how the upper atmosphere works—and verifying their accuracy—requires well-updated data about actual conditions in the sky. And the supply of that data is in danger of drying up, warns Mlynczak.
Most of the satellites that provided information from the upper atmosphere over the past three decades—which provided his and others' predictions of cooling and contraction—are reaching the end of their lives. Of the six NASA satellites in the briefcase, onefailedin December there was anotherdisassembledin March and three more will close soon. "No new missions are planned or underway yet," he says.
Mlynczak hopes to revive interest in monitoring with a special session he'll host this fall at the American Geophysical Union to discuss the upper atmosphere as "the next frontier in climate change." Without continued monitoring, the fear is that we may soon return to the days of ignorance.
FAQs
The upper atmosphere is cooling, causing new climate problems? ›
A new study reaffirming that global climate change is human-made also found the upper atmosphere is cooling dramatically because of rising CO2 levels. Scientists are worried about the effect this cooling could have on orbiting satellites, the ozone layer, and Earth's weather.
How is climate change affecting the upper atmosphere? ›Increased greenhouse gas concentrations cause global cooling in the middle and upper atmosphere (∼15−500 km altitude), causing this part of the atmosphere to shrink.
How does global cooling affect the climate? ›These have a direct effect: they effectively increase the planetary albedo, thus cooling the planet by reducing the solar radiation reaching the surface; and an indirect effect: they affect the properties of clouds by acting as cloud condensation nuclei.
What is happening to the temperature of the upper atmosphere? ›While still extremely thin, the gases of the thermosphere become increasingly denser as one descends toward the earth. As such, incoming high energy ultraviolet and x-ray radiation from the sun begins to be absorbed by the molecules in this layer and causes a large temperature increase.
Is the upper atmosphere getting colder? ›In the same way, even as the lower atmosphere is warming, a new study found that the Earth's upper atmosphere is actually cooling due to rising carbon dioxide levels and changes in the magnetic field. America is changing faster than ever!
What is causing the global cooling? ›The global cooling might be the result of the changes in oceanic circulation and atmospheric CO2, both probably influencing each other and possibly initiated by tectonic processes.
Is Earth getting colder or hotter? ›Highlights. Earth's temperature has risen by an average of 0.14° Fahrenheit (0.08° Celsius) per decade since 1880, or about 2° F in total. The rate of warming since 1981 is more than twice as fast: 0.32° F (0.18° C) per decade.
Is climate change causing cooling? ›Despite short-term decreases in global temperature, the long-term trend shows that Earth continues to warm.
Is any part of the world getting colder? ›It's a strange tale of two hemispheres. New research shows the Pacific hemisphere is losing heat faster than the African hemisphere. The heat is from Earth's molten interior, which causes continental drift.
When was the last global cooling period? ›Earth has experienced cold periods (informally referred to as “ice ages,” or "glacials") and warm periods (“interglacials”) on roughly 100,000-year cycles for at least the last 1 million years. The last of these ice age glaciations peaked* around 20,000 years ago.
What does the upper atmosphere do? ›
These layers protect our planet by absorbing harmful radiation.
What is the weather like in the upper atmosphere? ›Because of this, the top of the thermosphere can be found anywhere between 500 and 1,000 km (311 to 621 miles) above the ground. Temperatures in the upper thermosphere can range from about 500° C (932° F) to 2,000° C (3,632° F) or higher. The aurora, the Northern Lights and Southern Lights, occur in the thermosphere.
What happens in the upper layer of the atmosphere? ›Exosphere. This is the outermost layer of the atmosphere. It extends from about 375 miles (600 km) to 6,200 miles (10,000 km ) above the earth. In this layer, atoms and molecules escape into space and satellites orbit the earth.
Is the center of the Earth getting cooler? ›The planet's core has been cooling for billions of years but perhaps "more rapidly than expected," which could expedite the end of life on Earth — though not for quite a while.
Why is the stratosphere getting cooler? ›Cooling of the stratosphere isn't just the result of ozone destruction but is also caused by the release of carbon dioxide in the troposphere. Therefore, global warming in the troposphere and stratospheric cooling due to ozone loss are parallel effects.
Why is the upper atmosphere rarer? ›As we go higher the density of the particles in the upper layers of the atmosphere decreases progressively. As a result, the upper layers of the atmosphere are rarer than the lower layer.
Can global warming be reversed? ›Yes. While we cannot stop global warming overnight, we can slow the rate and limit the amount of global warming by reducing human emissions of heat-trapping gases and soot (“black carbon”).
Are we still in an ice age? ›Striking during the time period known as the Pleistocene Epoch, this ice age started about 2.6 million years ago and lasted until roughly 11,000 years ago. Like all the others, the most recent ice age brought a series of glacial advances and retreats. In fact, we are technically still in an ice age.
Is Antarctica warming or cooling? ›Antarctica seems to be both warming around the edges and cooling at the center at the same time. Sea ice extent surrounding Antarctica has trended higher since satellite measurements began in 1979. The central and southern parts of the west coast of the Antarctic Peninsula have warmed by nearly 3 °C.
Is global warming causing colder winters? ›No. Scientists say that severe winter weather is still to be expected from time to time. That kind of weather happens even during a long-term warming trend for the planet.
Will the Earth ever fully cool? ›
It took millions of years for the Earth to cool down and evolve into a habitable world. However, far beneath our feet, the Earth is still hot with one layer of molten metal, nearly as hot as the Sun! And the cooling process is still ongoing, gradually continuing over time as we move towards the core of the Earth.
Will the Earth ever cool down? ›While that sounds pretty alarming, some estimates for the cooling of Earth's core see it taking tens of billions of years, or as much as 91 billion years. That is a very long time, and in fact, the Sun will likely burn out long before the core — in around 5 billion years.
Does global warming mean it's warming everywhere? ›Global warming means Earth's annual average air temperature is rising over long time spans (many decades to centuries), but not necessarily in every location and not necessarily in all seasons.
What are the 5 causes of climate change? ›- Generating power. Generating electricity and heat by burning fossil fuels causes a large chunk of global emissions. ...
- Manufacturing goods. ...
- Cutting down forests. ...
- Using transportation. ...
- Producing food. ...
- Powering buildings. ...
- Consuming too much.
Rather, it is extremely likely (> 95%) that human activities have been the dominant cause of that warming. Human activities have contributed substantially to climate change through: Greenhouse Gas Emissions. Reflectivity or Absorption of the Sun's Energy.
What are the 10 warmest years on record? ›- 2019.
- 2017.
- 2015.
- 2022 (tied with 2015)
- 2018.
- 2021 (tied with 2018)
- 2014.
- 2010.
Why is winter warming so fast? The more greenhouse gasses in the atmosphere, such as carbon dioxide and methane, the warmer our world gets. Globally, the fastest warming occurs in colder regions, during colder seasons and colder times of the day.
What was Earth's warmest period? ›One of the warmest times was during the geologic period known as the Neoproterozoic, between 600 and 800 million years ago. Conditions were also frequently sweltering between 500 million and 250 million years ago.
When was global warming at its peak? ›Not only was 1998-2012 the warmest 15-year period on record at the time, but greenhouse gases continued to climb to new record highs, and other climate indicators continued to show the impacts of long-term, global-scale warming: subsurface ocean heating, global sea level rise, the melting of glaciers and ice sheets, ...
What warmed the Earth after the ice age? ›"CO2 was the big driver of global warming at the end of the Ice Age." Shakun and his colleagues started by creating the first global set of temperature proxies—a set of 80 different records from around the world that recorded temperatures from roughly 20,000 years ago to 10,000 years ago.
Can you breathe in the upper atmosphere? ›
The point where the troposphere ends and the stratosphere begins (also known as the tropopause) is the altitude at which temperatures no longer decrease as height increases. The air in the stratosphere is incredibly thin and very dry - humans would absolutely not be able to survive by breathing this air.
Does anything live in the upper atmosphere? ›Yet scientists are finding that a rich variety of life—archaea, bacteria, and single-celled eukaryotes—can thrive at high altitudes. In the troposphere, where day-to-day weather happens, each cubic meter of cloud contains on average tens of thousands of microbial cells.
What is the upper atmosphere constantly bombed by? ›High-energy cosmic rays (from outside the solar system) are constantly bombarding the upper atmosphere. These high-energy particles undergo a whole cascade of nuclear reactions resulting in some slow moving neutrons.
Is there oxygen in the upper atmosphere? ›The Stratospheric Observatory for Infrared Astronomy (SOFIA) made the first-ever measurement of heavy atomic oxygen in Earth's upper atmosphere. Measurements of heavy oxygen have implications on climate change, atmospheric science, and potential future exoplanet studies.
Is there water in the upper atmosphere? ›Quite simply, there's billions of gallons of water — mostly in the form of vapor — in the skies right now, and if it all fell at once, it would cause some major problems for millions of people. Related: Why does Earth have an atmosphere?
Does the upper atmosphere have oxygen? ›A study of the upper atmosphere's composition has successfully measured an increased presence of the oxygen-18 isotope (18O) — a type of oxygen whose atoms contain 10 neutrons instead of the eight neutrons found in oxygen-16 (16O), the most common isotope.
How is ozone destroyed in the upper atmosphere? ›Ozone Depletion. When chlorine and bromine atoms come into contact with ozone in the stratosphere, they destroy ozone molecules. One chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere. Ozone can be destroyed more quickly than it is naturally created.
What happens if the Earth's core cools down? ›When the Earth's core cools and solidifies, researchers say, that magnetic field will disappear and the planet will become similar to Mars, “affecting every planetary process as we know it,” TWC India's Mrigakshi Dixit reported.
What would happen if the Earth was cooling? ›A cooler Earth means less water would be evaporating from its surfaces into the atmosphere, changing rainfall patterns. This could produce ripple effects across the world's ecosystems – but the exact nature of these effects depends on how SAI is used.
Are humans getting cooler? ›According to the researchers, there are several reasons why our bodies might be cooling down. One is improvements in temperature regulation. “We have air conditioning and heating, so we live more comfortable lives at a consistent 68°F to 72°F in our homes,” Parsonnet explains.
Does global warming affect stratosphere? ›
While greenhouse gases absorb heat at a relatively low altitudes and warm the surface, they actually cool the stratosphere.
Does the stratosphere affect climate? ›Weather systems develop and exist in the troposphere (the lowest layer of the atmosphere). Above this layer lies the stratosphere, which, as the name implies, is highly stratified, stable and dry. It is not directly involved in the development of daily weather.
Can carbon dioxide cool the Earth? ›Since carbon dioxide also efficiently emits heat, any heat captured by carbon dioxide sooner escapes to space than it finds another molecule to absorb it. As a result, an increase in greenhouses gases like carbon dioxide means more heat is lost to space — and the upper atmosphere cools.
Where is Earth's atmosphere richest? ›Earth's atmosphere is richest in :
The correct answer is Option B. Earth 's atmosphere is richest in infrared radiation or IR. * The earth emits huge amounts of infrared radiation and thereby makes the atmosphere richest in infrared rays.
A large planet such as Jupiter has enough gravity to hold on to most of its hydrogen and helium, which is why these elements dominate the atmospheres of gas giants. But the gravity of Earth isn't strong enough, so Earth's early atmosphere of helium and free hydrogen evaporated into space.
What is the upper atmosphere limit? ›The ionosphere is a critical link in the chain of Sun-Earth interactions. This region is what makes radio communications possible. This is the upper limit of our atmosphere. It extends from the top of the thermosphere up to 10,000 km (6,200 mi).
What is effect of carbon dioxide on the upper atmosphere? ›Carbon dioxide in the atmosphere warms the planet, causing climate change. Human activities have raised the atmosphere's carbon dioxide content by 50% in less than 200 years.
What happens to CO2 in the upper atmosphere? ›Carbon dioxide (CO2), after it is emitted into the atmosphere, is firstly rapidly distributed between atmosphere, the upper ocean and vegetation. Subsequently, the carbon continues to be moved between the different reservoirs of the global carbon cycle, such as soils, the deeper ocean and rocks.
What part of the atmosphere does climate change affect? ›Warming temperatures are expanding the troposphere. The troposphere (seen here in orange) is the lowest layer of Earth's atmosphere and where nearly all weather occurs. Over the last 40 years, the boundary between the troposphere and the neighboring stratosphere (pink) has risen as a result of climate change.
Does the greenhouse effect affect the upper or lower atmosphere? ›Carbon dioxide in the lower atmosphere helps trap heat from the sun's solar energy reflected off the Earth's surface and so, like a greenhouse, the lower atmosphere grows warmer.
How is the upper atmosphere cooling? ›
Since carbon dioxide also efficiently emits heat, any heat captured by carbon dioxide sooner escapes to space than it finds another molecule to absorb it. As a result, an increase in greenhouses gases like carbon dioxide means more heat is lost to space — and the upper atmosphere cools.
Is the sun not CO2 to blame for global warming? ›No. The Sun can influence Earth's climate, but it isn't responsible for the warming trend we've seen over recent decades. The Sun is a giver of life; it helps keep the planet warm enough for us to survive.
What are the effects of stratospheric cooling? ›A direct effect of lower temperatures in the stratosphere is a change in the rates of some of the chemical reactions which control the ozone layer. Anthropogenic release of carbon dioxide may therefore lead to changes in the ozone layer in the future.
How do you remove CO2 from the upper atmosphere? ›Potential solutions include leveraging photosynthesis in coastal plants, seaweed, or phytoplankton; adding certain minerals to seawater that react with dissolved CO2 and lock it away; or running an electric current through seawater to accelerate reactions that ultimately help extract CO2.
Which layer of atmosphere is responsible for the climate change? ›Most of the visible clouds in the sky are in the troposphere. Extending up to 10 miles above Earth's surface, the troposphere contains a variety of gases: water vapor, carbon dioxide, methane, nitrous oxide, and others. These gases help retain heat, a portion of which warms the surface of Earth (greenhouse effect).
Where is climate change affecting the most? ›1) South Sudan – Floods & Drought
We planted maize in June but in July everything was under the water. We lost all the crops.” As one of the most rapidly warming areas in the world, South Sudan is on the frontlines of the climate crisis.
Greenhouse gases (GHGs) are a set of gases that accumulate in the lower layer of the atmosphere, the troposphere, and absorb infrared radiation, which contributes to increasing the average temperature of the Earth's surface [8].
What would the Earth temperature be without the greenhouse gases? ›'Greenhouse gases' are crucial to keeping our planet at a suitable temperature for life. Without the natural greenhouse effect, the heat emitted by the Earth would simply pass outwards from the Earth's surface into space and the Earth would have an average temperature of about -20°C.
What is the glass house effect? ›The greenhouse effect is the way in which heat is trapped close to Earth's surface by “greenhouse gases.” These heat-trapping gases can be thought of as a blanket wrapped around Earth, keeping the planet toastier than it would be without them.