What a load of tripe. If you can't be serious then don't bother to reply.
Climate: The Movie
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You seem to be doing exactly what you claim no one should be doing.
You said that you want to tax carbon. I assume you meant CO2. So which CO2 do you want to tax? It will help if you are more clear in your posting rather than expecting people to read your mind.
Also, what sacrifices are you making?
Would I be right in saying: none?
See, I don't have a problem with fossil fuels. I am very grateful we have them and I am grateful for all the products in my home that make life more civilized. All the metals, plastics, paints, electrical components. All exist thanks to the use of fossil fuels. Modern transportation, medicine, food. The only countries that either don't use fossil fuels or not much are extremely poor and people die young.
We should definitely protect the environment as much as we can and this country has done a lot.
So my conscience is clear. Especially because I am not persuaded that there is any climate emergency happening.
But for you, it is surely different? You are either making significant sacrifices, or you will know deep down that you are really a fraud. And a bad person. I do not envy you.
Betty3000 is persuaded by misinformation and myths
There is a climate emergency happening, the matter is settled.
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Myths about climate change
Global temperatures are now at their highest since records began. In fact, the 10 warmest years on Earth, since 1880, have occurred since 2014.[1]
So, when people talk about climate change today, they mean anthropogenic (human-made) climate change. This is the warming of Earth’s average temperature as a result of human activity, such as burning coal, oil and gas to produce energy to fuel our homes and transport, and cutting down trees to produce the food we eat
There is also an important distinction between weather and climate. Weather refers to short-term changes in the Earth’s atmosphere and represents things such as temperature, rain and cloudiness. Climate refers to longer-term changes in the Earth’s atmosphere over extended periods of time. Short-term changes in the weather will continue and that is why we can still experience cold snaps, despite the fact that the Earth’s temperature is warming. On top of this, we will keep on experiencing natural seasonal variations as the Earth orbits around the sun, so winter will continue to feel cooler than summer, even though the overall temperature is higher than it was 100 years ago.
The evidence shows that extreme heatwaves have increased since the 1950s and human-induced climate change is the main driver; with every additional increment of global warming, these extremes continue to increase.
Because climate change creates warmer and drier conditions, even if a wildfire is started as a result of human activity, there is more fuel available when vegetation is very dry, and the relative humidity of the air will be lower, allowing fires to spread further and faster. In addition, the global wildfire season is getting longer, due to higher temperatures and longer droughts.
A lot of the products we purchase in the UK are manufactured in China, meaning that we are essentially transferring a large portion of our emissions to the countries responsible for creating the products we use. Part of the reason emissions from highly industrialised countries are so high is because of the high demand for products created by them, from countries such as the UK.
Despite being one of the largest emitters of greenhouse gases today, in part because it’s such a big country, China’s emissions per person are less than other countries like the United States.
China is also currently investing heavily in renewable energy. The increase in investment has been in response to the rapid growth of green business, the demand for renewable energy and the need to clean up air pollution in its major cities.
MYTH 1. THE EARTH’S CLIMATE HAS ALWAYS CHANGED
Over the course of Earth’s 4.5-billion-year history, the climate has changed a lot, this is true. However, the rapid warming we’re seeing now can't be explained by natural cycles of warming and cooling. The kind of changes that would normally happen over hundreds of thousands of years are happening in decades.Global temperatures are now at their highest since records began. In fact, the 10 warmest years on Earth, since 1880, have occurred since 2014.[1]
So, when people talk about climate change today, they mean anthropogenic (human-made) climate change. This is the warming of Earth’s average temperature as a result of human activity, such as burning coal, oil and gas to produce energy to fuel our homes and transport, and cutting down trees to produce the food we eat
MYTH 2. GLOBAL WARMING ISN'T REAL AS IT'S STILL COLD
Global warming is causing the Earth’s average surface temperature to rise which, in turn, is causing changes in our natural climate systems. These changes are making all sorts of extreme weather events more likely and more severe, including more intense droughts, heatwaves and hurricanes but also, strangely, an increased potential for more severe cold weather eventsThere is also an important distinction between weather and climate. Weather refers to short-term changes in the Earth’s atmosphere and represents things such as temperature, rain and cloudiness. Climate refers to longer-term changes in the Earth’s atmosphere over extended periods of time. Short-term changes in the weather will continue and that is why we can still experience cold snaps, despite the fact that the Earth’s temperature is warming. On top of this, we will keep on experiencing natural seasonal variations as the Earth orbits around the sun, so winter will continue to feel cooler than summer, even though the overall temperature is higher than it was 100 years ago.
MYTH 3. HEATWAVES AND WILDFIRES HAVE NOTHING TO DO WITH CLIMATE CHANGE
Climate change makes extreme weather more frequent and intense, including heatwaves, wildfires and floods.The evidence shows that extreme heatwaves have increased since the 1950s and human-induced climate change is the main driver; with every additional increment of global warming, these extremes continue to increase.
Because climate change creates warmer and drier conditions, even if a wildfire is started as a result of human activity, there is more fuel available when vegetation is very dry, and the relative humidity of the air will be lower, allowing fires to spread further and faster. In addition, the global wildfire season is getting longer, due to higher temperatures and longer droughts.
MYTH 4. CHINA IS MOSTLY RESPONSIBLE FOR CLIMATE CHANGE
Human-induced climate change is something that has been happening for many years and Western countries, like the UK, have played a big role in contributing to carbon emissions over the past 200 years. This means that only looking at who the biggest emitters of greenhouse gases are today is an oversimplification of a very nuanced topic.A lot of the products we purchase in the UK are manufactured in China, meaning that we are essentially transferring a large portion of our emissions to the countries responsible for creating the products we use. Part of the reason emissions from highly industrialised countries are so high is because of the high demand for products created by them, from countries such as the UK.
Despite being one of the largest emitters of greenhouse gases today, in part because it’s such a big country, China’s emissions per person are less than other countries like the United States.
China is also currently investing heavily in renewable energy. The increase in investment has been in response to the rapid growth of green business, the demand for renewable energy and the need to clean up air pollution in its major cities.
So first you say its never been higher then you admit it has .
How dumb are you really ? do you have to practise or does it come naturally
It's a gift.
No
I said your assertion was wrong
just because Co2 was higher at tens of thousands of years ago does not disprove rise in co2 in the last 150 ears is not manmade or not the reason for temperature rise, it is.
I am sorry you are unable to grasp the most simple of concepts.
oh look its Frilly, the person who watches a "documentary" about climate change and believes the nonsense in it because he hasnt the skill nor intellect to do the most basic of research
dont be easily brainwashed like filly
Betty says he would like to apologise for the misinformation he has been posting and would like to post some actual facts instead
1.Myth: The climate isn’t really changing.
Fact: The world is warming at an unprecedented rate. Data collected from all over the world confirms that the decade from 2000 to 2009 was the warmest on record, and the Northern Hemisphere in particular is warmer than it has been in 1,300 years.
2.Myth: The Earth’s climate has changed before; it’s just part of a natural cycle.
Fact: The Earth’s climate has changed many times but never so rapidly. Also, the fact that the earth’s climate has changed before is evidence that human beings are affecting it now – because the climate has been shown to be sensitive to whatever forces it to change; in this case, it is human activity. Carbon dioxide levels in the atmosphere are the highest they have been for 800,000 years.
3.Myth: Human beings aren’t responsible for changing the Earth’s climate.
Fact: Those raised levels of carbon dioxide? Using a form of carbon dating, testing isotopes of carbon in CO2 particles in the atmosphere to find their source, scientists have confirmed that they have come from the burning of fossil fuels. So yes, human beings are responsible. There’s even a term for it: anthropogenic (human-caused) climate change.
4.Myth: Scientists don’t agree about climate change; the jury’s still out.
Fact: The vast majority of scientists, including many in prominent scientific institutions, agree on three things: the world is warming at an unprecedented rate; human activity, specifically the burning of fossil fuels, is the primary cause of that warming; and urgent action is required to address this. As The Climate Institute puts it, “There is consensus among scientists that the climate is being changed by human activity, in the same way as there is consensus on the existence of gravity or that the Earth is round.”
5.Myth: Some places are colder than usual – so much for global “warming”.
Fact: People often confuse weather (localised, atmospheric changes that vary by the hour) with climate (average conditions that prevail over years, decades, centuries, millennia). So observations that certain places are colder than normal don’t mean the Earth’s climate isn’t warming. What matters are changes in, for example, global average air temperatures, which are rising, thanks to higher than normal levels of carbon dioxide (CO2) and other greenhouse gases in our atmosphere.
6. Myth: It’s the sun.
Fact: Changes in the sun’s activity can’t explain the rise in global temperatures in recent decades. If global warming was due to the sun, all layers of our atmosphere would be warming. In fact, only the surface and lower atmosphere are warming (because CO2 and other greenhouse gases are trapping heat there); the upper layers, on the other hand, are cooling. Also, the sun has been exceptionally cool for the past 35 years, whereas global average temperatures have continued to rise.
7.Myth: Volcanoes emit more carbon dioxide than human beings ever could.
Fact: The world’s volcanoes emit less than one per cent of the carbon dioxide that humans put into the atmosphere in a year, and that percentage is dropping as human emissions increase annually. To put this in perspective: submarine (underwater) volcanoes can emit as much as 97 million tonnes of CO2 a year and volcanoes on land emit about 242 million tonnes of CO2 a year; human activity generates 29 billion tonnes of CO2 (and rising) a year.
8. Myth: Carbon dioxide is natural and essential for life, not a pollutant.
Fact: Even naturally occurring substances can become dangerous in some situations. Oxygen, for instance, is natural and we need it to survive but it becomes poisonous in high concentrations. Similarly carbon dioxide – along with methane, nitrous oxide and other artificial greenhouse gases – is heating up the atmosphere to what is now agreed to be a dangerous extent.
9.Myth: Some glaciers are growing, not shrinking.
Fact: While glaciers can grow and shrink depending on localised weather conditions, the World Glacier Monitoring Service has collected data from hundreds of glaciers around the world and found that as the world heats up, it is fast losing ice, which is affecting global sea levels as glacial meltwater flows into the world’s oceans.
10.Myth: A warmer climate might not be a bad thing.
Fact: Some places, say in the higher latitudes, might benefit in the short term from a warmer climate but everything in nature (including us) is interconnected. So no matter where you live, you’ll be affected by radical changes to the global landscape within the next few decades – and not gradually but suddenly – which is going to put increasing pressure on an already overpopulated world.
There’s one more myth: that we are powerless to do anything to stop or slow climate change. The fact is that human beings are intelligent, inventive and adaptable creatures. This challenge is within our grasp if we act now – as governments, communities, families and individuals. Everyone can do something. And we must.
this is probably too technical for you to read......
7. Is the current level of atmospheric CO2 concentration unprecedented in Earth’s history?
The present level of atmospheric CO2 concentration is almost certainly unprecedented in the past million years, during which time modern humans evolved and societies developed. The atmospheric CO2 concentration was however higher in Earth’s more distant past (many millions of years ago), at which time palaeoclimatic and geological data indicate that temperatures and sea levels were also higher than they are today.Measurements of air in ice cores show that for the past 800,000 years up until the 20th century, the atmospheric CO2 concentration stayed within the range 170 to 300 parts per million (ppm), making the recent rapid rise to more than 400 ppm over 200 years particularly remarkable [figure 3]. During the glacial cycles of the past 800,000 years both CO2 and methane have acted as important amplifiers of the climate changes triggered by variations in Earth’s orbit around the Sun. As Earth warmed from the last ice age, temperature and CO2 started to rise at approximately the same time and continued to rise in tandem from about 18,000 to 11,000 years ago. Changes in ocean temperature, circulation, chemistry, and biology caused CO2 to be released to the atmosphere, which combined with other feedbacks to push Earth into an even warmer state.
For earlier geological times, CO2 concentrations and temperatures have been inferred from less direct methods. Those suggest that the concentration of CO2 last approached 400 ppm about 3 to 5 million years ago, a period when global average surface temperature is estimated to have been about 2 to 3.5°C higher than in the pre-industrial period. At 50 million years ago, CO2 may have reached 1000 ppm, and global average temperature was probably about 10°C warmer than today. Under those conditions, Earth had little ice, and sea level was at least 60 metres higher than current levels.
Figure 3. Data from ice cores have been used to reconstruct Antarctic temperatures and atmospheric CO2 concentrations over the past 800,000 years. Temperature is based on measurements of the isotopic content of water in the Dome C ice core. CO2 is measured in air trapped in ice, and is a composite of the Dome C and Vostok ice core. The current CO2 concentration (blue dot) is from atmospheric measurements. The cyclical pattern of temperature variations constitutes the ice age/ interglacial cycles. During these cycles, changes in CO2 concentrations (in blue) track closely with changes in temperature (in orange). As the record shows, the recent increase in atmospheric CO2 concentration is unprecedented in the past 800,000 years. Atmospheric CO2 concentration surpassed 400 ppm in 2016, and the average concentration in 2019 was more than 411 ppm. Source: Based on figure by Jeremy Shakun, data from Lüthi et al., 2008 and Jouzel et al., 2007.
The Earth’s climate has been quite stable over the past 11,000 years, playing an important role in the development of human civilisation.
Prior to that, the Earth experienced an ice age lasting for tens of thousands of years. The past million years of the Earth’s history has been characterised by a series of ice ages broken up by relatively short periods of warmer temperatures.
These ice ages are triggered and ended by slow changes in the Earth’s orbit. But changing atmospheric concentrations of CO2 also plays a key role in driving both cooling during the onset of ice ages and warming at their end.
The global average temperature was around 4C cooler during the last ice age than it is today. There is a real risk that, if emissions continue to rise, the world warms more this century than it did between the middle of the last ice age 20,000 years ago and today.
In this explainer, Carbon Brief explores how the last ice age provides strong evidence of the role CO2 plays as a “control knob” for the Earth’s climate. It also acts as a cautionary tale of how the climate can experience large changes from relatively small outside “forcings”.
These ice ages are punctuated by “interglacial” periods where temperatures rise to around current levels. The most recent ice age occurred between 120,000 and 11,500 years ago, while the current interglacial period – the Holocene – is expected to last for additional tens of thousands of years (and human activity may inadvertently delay the start of the next ice age even further).
Ice-age cycles are primarily driven by periodic changes in the Earth’s orbit. Three distinct orbital cycles – called Milankovitch cycles after their discoverer, Serbian scientist Dr Milutin Milankovitch – interact to change the distribution of incoming solar energy in ways that can dramatically affect the Earth’s climate.
Illustration of the three Milankovitch cycles from the COMET Program at the University Center for Atmospheric Research.
These include:
When these cycles cause the northern latitudes to get less sun in the summer, it allows ice sheets to begin to expand. These ice sheets in turn reflect more incoming sunlight back to space, resulting in a “positive feedback” that drives additional regional cooling.
The northern latitudes matter much more than the southern latitudes – at least over the past few million years – as it contains more land area (which can more easily become ice-covered than the oceans) and because the Antarctic has remained covered in ice.
Changes in atmospheric greenhouse gas concentrations – and, in particular, CO2 – play a large role in the development of cold conditions during ice ages and warm conditions during interglacial periods. In this case, CO2 is not the immediate cause of ice ages; rather, it serves as a feedback to amplify changes initiated by orbital variations.
Prior to that, the Earth experienced an ice age lasting for tens of thousands of years. The past million years of the Earth’s history has been characterised by a series of ice ages broken up by relatively short periods of warmer temperatures.
These ice ages are triggered and ended by slow changes in the Earth’s orbit. But changing atmospheric concentrations of CO2 also plays a key role in driving both cooling during the onset of ice ages and warming at their end.
The global average temperature was around 4C cooler during the last ice age than it is today. There is a real risk that, if emissions continue to rise, the world warms more this century than it did between the middle of the last ice age 20,000 years ago and today.
In this explainer, Carbon Brief explores how the last ice age provides strong evidence of the role CO2 plays as a “control knob” for the Earth’s climate. It also acts as a cautionary tale of how the climate can experience large changes from relatively small outside “forcings”.
Milankovitch cycles
The Earth has experienced a number of periods over the past million years in which large continental ice sheets have covered much of the northern hemisphere. These ice ages are associated with a large drop in global temperatures – 4C or more below today’s levels – with much larger changes over land and in the high latitudes.These ice ages are punctuated by “interglacial” periods where temperatures rise to around current levels. The most recent ice age occurred between 120,000 and 11,500 years ago, while the current interglacial period – the Holocene – is expected to last for additional tens of thousands of years (and human activity may inadvertently delay the start of the next ice age even further).
Ice-age cycles are primarily driven by periodic changes in the Earth’s orbit. Three distinct orbital cycles – called Milankovitch cycles after their discoverer, Serbian scientist Dr Milutin Milankovitch – interact to change the distribution of incoming solar energy in ways that can dramatically affect the Earth’s climate.
Illustration of the three Milankovitch cycles from the COMET Program at the University Center for Atmospheric Research.
These include:
- Precession – a 26,000-year shift in the orientation of Earth’s axis of rotation that affects how much summer sun is received at high latitudes (and shifting how much reaches the north vs south).
- Obliquity – a 41,000-year change in the tilt of the Earth’s axis relative to the sun that changes how much sun is received during a year at the poles versus the equator.
- Eccentricity – a 100,000-400,000 change in the shape of the Earth’s orbit around the sun that alters the length of the seasons and affects the importance of precession.
When these cycles cause the northern latitudes to get less sun in the summer, it allows ice sheets to begin to expand. These ice sheets in turn reflect more incoming sunlight back to space, resulting in a “positive feedback” that drives additional regional cooling.
The northern latitudes matter much more than the southern latitudes – at least over the past few million years – as it contains more land area (which can more easily become ice-covered than the oceans) and because the Antarctic has remained covered in ice.
Greenhouse gases
These shifts in the distribution of sun’s energy across the Earth’s surface are not enough to explain the dramatic changes to the climate during ice ages, particularly outside high-latitude regions.Changes in atmospheric greenhouse gas concentrations – and, in particular, CO2 – play a large role in the development of cold conditions during ice ages and warm conditions during interglacial periods. In this case, CO2 is not the immediate cause of ice ages; rather, it serves as a feedback to amplify changes initiated by orbital variations.
The hockey stick -this is a go to argument pushed by climate change deniers
Since its publication, the paper has been attacked by greenhouse skeptics, and its methods have been criticized by various mathematicians. However, the National Academy of Sciences and the Intergovernmental Panel on Climate Change (IPCC) have both asserted that the graph is, despite uncertainties, an essentially correct picture of global temperature over at least the last 1,000 to 1,300 years.
In their 1998 paper, Mann and his colleagues cite data from multiproxy (many-proxy) studies using ice cores, glacial melting, written historical records, tree rings, coral layers, and other sources of information about past climate. Such work had been done by other scientists before, but Mann, Bradley, and Hughes were the first to assemble records into a single chart spanning such a long time period. A version of the graph appeared in the Third Assessment Report of the IPCC in 2001, the United Nations-based organization's summary of the state of scientific knowledge about climate change.
Scientific papers criticizing the graph began appearing in 2003. A paper by W. Soon and S. Baliunas argued that a warm interval in the Middle Ages called the Medieval Warm Epoch was roughly equivalent to today's warming; S. McIntyre and R. McKitrick stated that they could not reproduce the hockey stick graph using Mann et al.'s original multiproxy data. In 2004, Hans von Storch argued in Science that Mann's group had underestimated the amount of variation in past climate by a factor of two, which would tend to make it less likely that today's rising temperatures are truly unusual. In 2005, McIntyre and McKitrick claimed that they could produce the hockey-stick graph shape by using Mann et al.'s mathematical methods on noise (random data). If true, this would tend to show that the hockey stick graph is meaningless.
In 2005, the U.S. Congress asked the National Research Council's Board on Atmospheric Sciences and Climate, part of the National Academy of Sciences, to assemble a committee to examine the question of global temperatures over the last 2,000 years—essentially, to decide whether the hockey stick graph is a valid picture of climate change. A Committee on Surface Temperature Reconstructions for the Last 2,000 Years, containing 16 scientists, was formed. In 2006, the scientists released a book-length report on surface-temperature reconstruction. In it, they painstakingly reviewed all categories of proxy and instrumental (direct-measurement) data on atmospheric surface temperature.
The committee concluded that the hockey stick graph is essentially valid. “It can be said with a high level of confidence,” the committee wrote, “that global mean temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries.” However, it also noted that as one goes further back in time, uncertainty increases.
Hockey Stick Controversy
Introduction
In 1998, a paper authored by Michael E. Mann, Raymond S. Bradley, and Malcolm K. Hughes was published in the journal Nature. The authors reconstructed average air temperatures in the Northern Hemisphere from 1500 AD to the present using a number of different kinds of data. They included in their article a graph of these average Northern Hemisphere temperatures. The graph showed that, despite much up-and-down variability, the temperature rise seen in recent decades is unprecedented over the time period considered. The authors also concluded that human-released greenhouse gases, especially carbon dioxide, were almost certainly the cause of the recent global warming. In 1999, Mann published a version of the graph going back 1,000 years. The temperature curve of both graphs is relatively flat for most of its length, then shoots up suddenly at the right-hand end (marking the recent past to the present), resembling in outline a hockey stick laid on its side.Since its publication, the paper has been attacked by greenhouse skeptics, and its methods have been criticized by various mathematicians. However, the National Academy of Sciences and the Intergovernmental Panel on Climate Change (IPCC) have both asserted that the graph is, despite uncertainties, an essentially correct picture of global temperature over at least the last 1,000 to 1,300 years.
Historical Background and Scientific Foundations
Mann, Bradley, and Hughes are neither the first nor the last scientists to reconstruct past temperature proxy data, that is, from measurements of phenomena such as tree-ring thicknesses that show temperature indirectly. Proxy data are needed for periods longer than about 150 years ago because no precise weather measurements were recorded before that time.In their 1998 paper, Mann and his colleagues cite data from multiproxy (many-proxy) studies using ice cores, glacial melting, written historical records, tree rings, coral layers, and other sources of information about past climate. Such work had been done by other scientists before, but Mann, Bradley, and Hughes were the first to assemble records into a single chart spanning such a long time period. A version of the graph appeared in the Third Assessment Report of the IPCC in 2001, the United Nations-based organization's summary of the state of scientific knowledge about climate change.
Scientific papers criticizing the graph began appearing in 2003. A paper by W. Soon and S. Baliunas argued that a warm interval in the Middle Ages called the Medieval Warm Epoch was roughly equivalent to today's warming; S. McIntyre and R. McKitrick stated that they could not reproduce the hockey stick graph using Mann et al.'s original multiproxy data. In 2004, Hans von Storch argued in Science that Mann's group had underestimated the amount of variation in past climate by a factor of two, which would tend to make it less likely that today's rising temperatures are truly unusual. In 2005, McIntyre and McKitrick claimed that they could produce the hockey-stick graph shape by using Mann et al.'s mathematical methods on noise (random data). If true, this would tend to show that the hockey stick graph is meaningless.
In 2005, the U.S. Congress asked the National Research Council's Board on Atmospheric Sciences and Climate, part of the National Academy of Sciences, to assemble a committee to examine the question of global temperatures over the last 2,000 years—essentially, to decide whether the hockey stick graph is a valid picture of climate change. A Committee on Surface Temperature Reconstructions for the Last 2,000 Years, containing 16 scientists, was formed. In 2006, the scientists released a book-length report on surface-temperature reconstruction. In it, they painstakingly reviewed all categories of proxy and instrumental (direct-measurement) data on atmospheric surface temperature.
The committee concluded that the hockey stick graph is essentially valid. “It can be said with a high level of confidence,” the committee wrote, “that global mean temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries.” However, it also noted that as one goes further back in time, uncertainty increases.
wee bit too technical for you basic maths but 1,000, 000 is a mere blip in 5,400,000,000this is probably too technical for you to read......
7. Is the current level of atmospheric CO2 concentration unprecedented in Earth’s history?
The present level of atmospheric CO2 concentration is almost certainly unprecedented in the past million years, during which time modern humans evolved and societies developed. The atmospheric CO2 concentration was however higher in Earth’s more distant past (many millions of years ago), at which time palaeoclimatic and geological data indicate that temperatures and sea levels were also higher than they are today.
Measurements of air in ice cores show that for the past 800,000 years up until the 20th century, the atmospheric CO2 concentration stayed within the range 170 to 300 parts per million (ppm), making the recent rapid rise to more than 400 ppm over 200 years particularly remarkable [figure 3]. During the glacial cycles of the past 800,000 years both CO2 and methane have acted as important amplifiers of the climate changes triggered by variations in Earth’s orbit around the Sun. As Earth warmed from the last ice age, temperature and CO2 started to rise at approximately the same time and continued to rise in tandem from about 18,000 to 11,000 years ago. Changes in ocean temperature, circulation, chemistry, and biology caused CO2 to be released to the atmosphere, which combined with other feedbacks to push Earth into an even warmer state.
For earlier geological times, CO2 concentrations and temperatures have been inferred from less direct methods. Those suggest that the concentration of CO2 last approached 400 ppm about 3 to 5 million years ago, a period when global average surface temperature is estimated to have been about 2 to 3.5°C higher than in the pre-industrial period. At 50 million years ago, CO2 may have reached 1000 ppm, and global average temperature was probably about 10°C warmer than today. Under those conditions, Earth had little ice, and sea level was at least 60 metres higher than current levels.
Figure 3. Data from ice cores have been used to reconstruct Antarctic temperatures and atmospheric CO2 concentrations over the past 800,000 years. Temperature is based on measurements of the isotopic content of water in the Dome C ice core. CO2 is measured in air trapped in ice, and is a composite of the Dome C and Vostok ice core. The current CO2 concentration (blue dot) is from atmospheric measurements. The cyclical pattern of temperature variations constitutes the ice age/ interglacial cycles. During these cycles, changes in CO2 concentrations (in blue) track closely with changes in temperature (in orange). As the record shows, the recent increase in atmospheric CO2 concentration is unprecedented in the past 800,000 years. Atmospheric CO2 concentration surpassed 400 ppm in 2016, and the average concentration in 2019 was more than 411 ppm. Source: Based on figure by Jeremy Shakun, data from Lüthi et al., 2008 and Jouzel et al., 2007.
poor gas doesnt understand this:
Measurements of air in ice cores show that for the past 800,000 years up until the 20th century, the atmospheric CO2 concentration stayed within the range 170 to 300 parts per million (ppm), making the recent rapid rise to more than 400 ppm over 200 years particularly remarkable
dont be silly like gas
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