78

The IPCC do mentions solar minimums and maximums, as part of extremely careful treatment they do of the reconstructions and predictions for the changes in solar irradiance. The Assessment Report 5, Working Group 1, Chapter 8, have a whole section (~4 pages) dealing with solar irradiances. If the IPCC don't mention grand solar maximums/minumums that often, ...


76

In a nutshell: The radiation that enters is shortwave radiation from the sun. Solar radiation is dominated by visible (as well as UV and near infrared) radiation with a wavelength mostly between 0.2 µm and 2 µm. This wavelength is determined by the temperature of the Sun, in the order of 6000 K. For visible radiation (roughly between 0.4 µm and 0.7 µm), ...


71

The problem is the increase in the rate of sea level rise. I pulled out some approximate numbers from the figure you presented: Can you see now how the sea level is rising much faster today than a century ago? Sea level rise, as well as climate change are normal things on Earth history. However, most times they happen at a very slow rate, allowing ...


44

In 2010 anthropogenic emissions (not including land use change) were approximately 9167 million metric tonnes. Your data on trees holding 13 lbs (5.9 kg) of carbon per year equates to 169.6 trees per metric tonne of emissions. So to take up all of the emissions from 2010 you would need 1,545,000,000,000 trees. A mature forest has only about 100 trees ...


40

I think the main question has already been answered. But I would like to add to the fallacy that: History shows solar activity is the main driver of our climate, among other factors. The Sun is undoubtedly the main source of energy for the planet and its climate. However, variations in solar activity are not the main cause of variations in climate. The ...


39

Your question about water vapour is quite a common one among people learning about the greenhouse effect. Once you discover the relevant proportions of water vapour and CO2 in the atmosphere, it's perhaps natural to assume that the CO2 can't be playing a major role. In reality it doesn't work like this, for at least a couple of reasons. First, let's look at ...


38

I want to know if that article has been refuted anywhere Yes. You can read all about it in the blog post James Taylor misinterprets study by 180 degrees. In short, the original paper was designed to test the view of "professional geologists", which in this case are members of the Association of Professional Engineers and Geoscientists of Alberta. The vast ...


37

There looks like legitimate cause for further study, preferably by scientists breathing air under 950ppm CO2 (this study showing a 15% decline in cognitive ability at this level). Because it is not known what mechanisms are involved in this decline in cognitive ability it is not clear if there are threshold levels, with step changes in impacts or if the ...


35

Does human body temperature impact climate change? Directly? It's not even a blip. The Earth's population is 7.6 billion. With each person radiating about 80 watts (basal metabolism), that's about 600 gigawatts, or 760 gigawatts using a round figure of 100 watts. That sounds like a lot, but it's only a tiny fraction of the 18 terawatts consumed by humanity, ...


34

"So much work"? Actually, compared to the global rate of greenhouse gas emissions, it's a case of "so little work"! From a scientific perspective the 'economists' solution' of carbon trading was always unlikely to achieve the required carbon cuts, as has been verified by their ineffectiveness over the last decade or so. As farrenthorpe points out, the rate ...


32

Quoting from John Russell's response to this article, "This is arrant nonsense!" Russell concludes with How did this paper get through the peer-review and editorial review processes? What technical standards were applied to determine the apparent merit of its contents so as to justify its inclusion in a reputable journal? Just because something is ...


31

Using the latest numbers from the 2013 IPCC report (Ch. 4, the Cryosphere), Antarctica contains 58.3 m of sea level equivalent (sle) and Greenland 7.36 m sle. Remaining glaciers provide an additional 0.41 m sle. In total and adding very minor contributions from permafrost etc. the total comes out to approximately 66.1 m sle. EDIT: Just to be complete: If ...


28

There has always been a strong north-south rainfall gradient from approximately the Golan Heights (high rainfall), through Judaea and southwards into the arid Sinai desert. We know that this gradient once had a higher rainfall because there are abundant rainfall harvesting and groundwater collection structures, built by the Nabatean civilization about 400 BC ...


26

Firstly it is worth demonstrating that 97% of climate scientists agree that climate-warming trends over the past century are very likely due to human activities. W. R. L. Anderegg, “Expert Credibility in Climate Change,” Proceedings of the National Academy of Sciences Vol. 107 No. 27, 12107-12109 (21 June 2010); DOI: 10.1073/pnas.1003187107. P. T....


25

The sea is not the only thing that rises, the sea floor can also rise and fall in accordance with the underlying geology. Oceanic tectonic plates sink as they age (and thus get colder and denser), the Solomon islands happen to be on a sinking section of the ocean floor and at the same time the sea level is rising. Keep in mind many of those islands have a ...


23

The short answer is yes, it's possible. And it can also reduce harm. Summary of the changes Here's a brief summary of the changes that happen when electricity is generated from a wind turbine, rather than from a fossil or nuclear plant: energy is taken out of the wind further upwind than it would otherwise be there is more turbulence just downwind from ...


23

Your premises are flawed due to the lack of two critical details: Population rise; the sheer number of people on the planet that are consuming resources has risen to 7 billion people. Standard of Living; a greater percentage of people in the world live a "Western" style, which consumes more goods per capita. You should study something like the Global ...


23

Runaway climate change is, given our current state of knowledge, only something that could be confirmed in historic context - in the rear-view mirror. Inconveniently, there's likely to be a much-diminished version of human civilisation around to observe it, if and when it does happen. In other words, it's too early to tell if we've passed a catastrophic ...


23

Gerrit's got the technical answer; I'm going to answer for a layperson. There are two ways objects lose heat. The first, and the way people are most familiar with, is conduction. Something touches something else, and the hotter material transfers some of its heat to the colder material. It's why you rapidly lose heat if you wade into cold waters: your ...


22

As the abstract makes clear, the finding of Cook et al. (2013) is not really "97% of researchers agree..."; rather, it is "97% of peer-reviewed publications agree". They didn't just go through some directory of climate researchers asking them what they thought. They read the abstracts of all 11,944 publications they found on the topic, and classified them ...


21

Electricity from waves, from hydro (both run-of-river and storage) and from wind, are all indirect forms of solar power. Electricity from tides is different, and we can deal with that in a separate question. Global tidal electricity generation is not yet at the scale of gigawatts, so it's tiny for now. Winds come about from the sun heating different parts ...


21

The definitive place to start is the Summary for Policy Makers at the start of the IPCC AR5 Working Group 1 on the physical science basis of climate change. This also acts as a suitable introduction to the massive rest of the physical basis report, and will, together with the contents table for the full report, enable a reader to quickly find the sections ...


21

To add to Gerrit's excellent answer, I'd like to add a couple more Images. Images always help clarify things for me. Firstly, this one shows the spectrum light coming from the sun in red. The peak is in the visible range*. It also shows the thermal radiation from the earth in blue. This is in the infrared range. Below, it shows how different gases allow ...


19

I think you're slightly confused by some of the terminology. (Caveat: I'm a geophysist, take anything I say with a grain of salt!) We're currently in an interglacial during a prolonged period of icehouse climate (most of the Cenozoic). During most of the Earth's history, the overall climate tends to be much warmer and more stable on the million-year scale....


19

The paper is deeply flawed from both the climate science and machine learning perspectives. The most obvious being the most eye-catching claim that equilibrium climate sensitivity is approximately 0.6C, which if true would overturn our understanding of the climate system. However the paper doesn't actually explain how this figure of 0.6C is obtained from a ...


18

The paper you linked lists as its first reference Volokin and ReLlez, 2014; a paper that addresses the magnitude of the Earth's greenhouse effect. The validity of the paper you found largely hinges on the reputation of the Volokin and ReLlez, so we will investigate that one first. The science of Volokin and ReLlez The traditional way to determine the '...


17

First off, let me preface this answer with a disclaimer: I do not deny climate change. From what I've read, the skeptics for the most part don't claim to have an alternative explanation for the recent warming. Their arguments (not mine!) are fourfold: The recent warming doesn't exist, is natural, or is just noise. The tiny half degree warming we've seen in ...


17

I'm going to try to answer this, though it's actually a very hard question depending on how close you look at it. Lets start with the American Physical Society's statement on climate change - which, they've made an effort to balance out following their 2007 statement of "evidence is incontrovertible" that got some members upset and lead to a handful of ...


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