86

Yes it is logarithmic (although relative to amount of CO2 in a sample volume of gas, not its concentration). No that doesn't invalidate climate change. If you want to read a detailed explanation for both answers, please see Skeptical Science - Is the CO2 effect saturated?. The mistaken idea that the Greenhouse Effect is 'saturated', that adding more ...


47

There are at least three issues here which contribute to the large differences which Spencer describes. First, there's a highly misleading aspect to the chart. People not familiar with the subject, or who just glance at the chart quickly might conclude that experimental data show essentially no change even though all the climate models are predicting ...


35

No, it is not true that it invalidates climate change claims, or the need to limit further increases in CO2 concentration specifically as it relates to warming (we can ignore stuff like ocean acidification for this question to keep from wandering too far abroad). First of all, let's look at the source. Is the person an objective scientist, making claims ...


34

The paper does not claim that that 97% of scientists endorse AGW. The study was conducted to evaluate the consensus within the published literature, and it found that an overwhelming percentage of published papers expressing a view on the question do endorse the premise that human activity is causing global warming. Among abstracts expressing a position ...


30

Trends in solar radiation don't match up with trends in temperature. One of the arguments from skeptics of climate change is that rising global temperatures are a natural phenomenon caused by the Sun. However, most measures of total solar irradiance (also known as solar radiation, the electromagnetic energy incident on Earth's surface) show that, on the ...


27

Could sensitivity it be lower than 3°C for a doubling of CO2e? Yes, it could, as the IPCC have said in their assessment reports, and as the science has said for decades. This single new study suggests a range of 1-2.9°C, which has huge overlap with the IPCC range. It is therefore consistent with IPCC estimates, and while it adds new data and new ...


27

The claim that "... the effectiveness of CO2 as a greenhouse gas diminishes logarithmically with increasing concentration and from the current level of ~390 ppmv, ..." and that "inconvenient fact" is "well disguised for any lay reader" is one of the more ridiculous climate skeptic claims I've seen. The main metric used by climate scientists to describe the ...


26

Yes, climate is close to a tipping point: the increase in global heat content, brought about predominantly by increased concentrations of greenhouse gases, is now triggering positive feedbacks. Note that "positive feedbacks" is used here in the way it is used in control systems: the "positive" refers to an amplification effect: the feedback reinforces / ...


26

tl;dr- This claim is false and has been retracted. The figure shown in the claim is wrong because it used one data interpretation method before 2010 and then switched to another after that, causing a false trend. Update As explained in @DikranMarsupial's answer, the source of this claim has retracted it as mistaken. The website that hosted the original ...


24

If you do the arithmetic, the statement that struck you: We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. gives the 97%. You throw out the 66.4% that did not take a position since they provide no data on the question. 32.6 / (32.6 + 0.3 + 0....


24

The article quotes a scientific paper as saying: Hansen and colleagues have estimated that Earth's actual average surface air temperature between 1951 and 1980 was approximately 287 K (14 degrees Celsius) (Hansen et al. 2010). The quoted paper Hansen et al. 2010 is confirming a study done back in 1999. For the sake of users who require an absolute ...


22

Each CO2 molecule in the air would have to be 2,500°C This is wrong because molecules collide with each other, transferring their kinetic energy. As explained in Elements of Physical Chemistry by Atkins et al.: the collision frequency of a typical gas is about [1,000,000,000 times per second] at 1 atm and room temperature, so the time in flight in a gas ...


14

No, 97% of peer reviewed studies do not endorse that global warming is human caused The study found that 97% of abstracts about 'global climate' or 'global climate change', at least "Implied humans are causing global warming. E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause." versus abstracts that ...


12

Disconnect between journal article and the blog post on it The sketchy claim investigated in this question is: “By 2100, the earth at sea level could have atmospheric oxygen levels comparable to the top of Mount Everest today. And as far as I know, people cannot normally stay on Everest without oxygen masks for more than a few minutes,” Petrovskii said. ...


11

The first thing to point out is that "no statistically significant warming" does not mean that there has been no warming, essentially it just means that there hasn't been enough warming to rule out the possibility that there has been no warming. If that sounds counter-intuitive, it is because it is, but that is the way frequentist statistical hypothesis ...


11

The first part of the claim is: the effectiveness of CO2 as a greenhouse gas diminishes logarithmically with increasing concentration and from the current level of ~390 ppmv, (parts per million by volume). Accordingly only ~5% of the effectiveness of CO2 as a greenhouse gas remains beyond the current level. Expressions using logarithmic functions have ...


11

Since you were (apparently) thinking about line of research of David Zhang and his colleagues: yes they did find that cold weather historically promoted more wars and ultimately population decline, but they also found (2011) this was mediated by falling agricultural production: Although agricultural production decreased or stagnated in a cold climate, ...


11

tl;dr: There was a 4% increase in CO2 emissions from the residential sector due to demand for natural gas for heating. When adjusted for temperature, there was a decrease of around 1.5% Residential emissions The UK's open government data website provides annual data on greenhouse gas emissions by sector. In February 2020, the latest statistical data was ...


10

No, it is not accurate to say (based on that study) that 97% of experts agree that global warming is anthropogenic. One problem is that there are two different definitions of "consensus" being used. The original consensus claim used by the IPCC was that it was very likely that most of the recent warming (>50%) was caused by humans. When we say that "global ...


10

The following articles suggest that dinosaurs breathed efficiently, like birds do still: which allowed them to cope with low oxygen levels that killed off other species. Note that some birds are able to breathe and fly at 20,000 feet, where the oxygen is lower (less than half sea-level pressure). BBC Earth - Did all dinosaurs breathe like birds? BIRDS ...


10

Without geo-engineering solutions, a certain amount of warming is irreversible. Even if we stop emitting CO2 today, the energy is in the system and it will cause a certain amount of warming. Dr. James Hansen of NASA Goddard has talked a lot about this. He often says that there is already warming "in the pipeline" that is irreversible. In a 2005 ...


9

THE GREAT WIND OF APRIL 11-12, 1934, ON MOUNT WASHINGTON, N.H., AND ITS MEASUREMENT In the course of preparation of this paper, and in order to establish all the facts of such important records, arrangements were made with the cooperation of the Chief of the Weather Bureau and the Director of the Bureau of Standards to subject the anemometer to ...


8

No, it's not true. Here's a 60-second explanation of global warming. It's conservation of energy. Fourier asked in 1824: the earth receives a continuous stream of energy from the sun. Why doesn't it keep getting hotter and hotter? The answer is that the earth also radiates heat into space. A warmer object radiates more heat, so the earth warms up to a ...


8

note: This question was originally much longer and quoted section 1 of this response by The Heartland Institute. My comments here are in reference to those claims. The Heartland Institute's claims about conflict of interest policies and funding disclosure, at least, are incorrect. The conflict of interest policy for Science Bulletin states: Authors must ...


8

The claim made by the GWPF is directly contradicted by... the GWPF, the banner for their website shows the U.K. Met office's global temperature dataset, which shows that temperatures have obviously increased over the last decade. I've replotted the data below, using woodfortrees.org (They only have monthly rather than annual data, so I've used a 12 month ...


8

TL;DR Are global temps cooler today than in 2007? No, and even if they are (which they are not), that wouldn't mean anything. Climate change is about what happens over the course of multiple decades, not just one cherry-picked date in the recent past. Detailed answer: There are a number of issues with the above graph and the implication that 2007 ...


7

Easterbrooks main argument here has already been discussed at Skeptical Science, the article is here. There are two main errors, the first is to treat Greenland as if it were representative of global temperatures. The second, more important error is that apparently it is conventional in this field to treat 1950 as the "present" in this kind of study. ...


6

Climate can definitely be affected by the presence of mountains. One such occurrence is Rain Shadow, where the peak of the mountain causes the clouds that would normally pass over to raise in altitude, precipicate and rain back down before fully crossing over the mountain, leaving the air behind the mountain dryer. image by en:User:Bariot - en:File:...


6

Bill McKibben's article is based on a report by a team of writers for the LA Times and Inside Climate, who, in the interests of transparency, posted many of their documents here. Here's some of what they say. "Bad News" Letter (1978) Exxon must develop a credible scientific team that can critically evaluate the information generated on the subject and be ...


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