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Scientists Can Now Blame Individual Natural Disasters On Climate Change (scientificamerican.com)
In 2003, the predominant view in the scientific community was that there was no way to determine the exact influence of climate change on any individual event. "There are just too many other factors affecting the weather, including all sorts of natural climate variations," reports Scientific American. But Myles Allen, a climate expert at the University of Oxford, believes scientists can blame individual natural disasters on climate change. Scientific American reports of how extreme event attribution is one of the most rapidly expanding areas of climate science: Over the last few years, dozens of studies have investigated the influence of climate change on events ranging from the Russian heat wave of 2010 to the California drought, evaluating the extent to which global warming has made them more severe or more likely to occur. The Bulletin of the American Meteorological Society now issues a special report each year assessing the impact of climate change on the previous year's extreme events. Interest in the field has grown so much that the National Academy of Sciences released an in-depth report last year evaluating the current state of the science and providing recommendations for its improvement. And as the science continues to mature, it may have ramifications for society. Legal experts suggest that attribution studies could play a major role in lawsuits brought by citizens against companies, industries or even governments. They could help reshape climate adaptation policies throughout a country or even the world. And perhaps more immediately, the young field of research could be capturing the public's attention in ways that long-term projections for the future cannot.
In 2004, Allen and Oxford colleague Daithi Stone and Peter Stott of the Met Office co-authored a report that is widely regarded as the world's first extreme event attribution study. The paper, which examined the contribution of climate change to a severe European heat wave in 2003 -- an event which may have caused tens of thousands of deaths across the continent -- concluded that "it is very likely that human influence has at least doubled the risk of a heat wave exceeding this threshold magnitude." Before this point, climate change attribution science had existed in other forms for several decades, according to Noah Diffenbaugh, a Stanford University climate scientist and attribution expert. Until 2004, much of the work had focused on investigating the relationship between human activity and long-term changes in climate elements like temperature and precipitation. More recently, scientists had been attempting to understand how these changes in long-term averages might affect weather patterns in general.
In 2004, Allen and Oxford colleague Daithi Stone and Peter Stott of the Met Office co-authored a report that is widely regarded as the world's first extreme event attribution study. The paper, which examined the contribution of climate change to a severe European heat wave in 2003 -- an event which may have caused tens of thousands of deaths across the continent -- concluded that "it is very likely that human influence has at least doubled the risk of a heat wave exceeding this threshold magnitude." Before this point, climate change attribution science had existed in other forms for several decades, according to Noah Diffenbaugh, a Stanford University climate scientist and attribution expert. Until 2004, much of the work had focused on investigating the relationship between human activity and long-term changes in climate elements like temperature and precipitation. More recently, scientists had been attempting to understand how these changes in long-term averages might affect weather patterns in general.
This is a clickbait headline. Shame on Scientific American for posting that headline, and shame on Slashdot for following along.
Let's quote from farther down in the article:
Today, scientists still generally agree that it's impossible to attribute any individual weather phenomenon solely to climate change. Storms, fires, droughts and other events are influenced by a variety of complex factors. And they're all acting at once, including both natural components of the climate system and sometimes unrelated human activities. For instance, a wildfire may be made more likely by hot, dry weather conditions, and by human land-use practices.
This contradicts the headline. Scientists aren't blaming individual disasters on climate change.
Climate is the statistical distribution of weather, including the normals and extremes. In many cases, it follows the normal distribution. However, other distributions may be appropriate especially for certain variables like precipitation. The scientists are saying that climate change is causing the distributions to change, and they are quantifying how the distributions change. They can then say that a particular event is more or less likely to occur as a result of climate change, and that's what they're actually doing.
The article references three events that they say are "impossible" without climate change, one of which is http://www.ametsoc.net/eee/2016/ch3.pdf. This is a modeling study, basically integrating climate models forward with various forcings to test whether they could reproduce a given event. Because the model failed to reproduce the result over a period of 5,200 events absent anthropogenic forcing, they concluded that the event was impossible without anthropogenic forcing. While climate change may have made the event much more likely, the claims are probably misleading.
If you trust the model, you might be able to argue that the probability is less than 1/5200 of the event occurring in a given year (or something similar) given that the model failed to reproduce the result. It's probably much less than 1/5200, based on this statement:
However, simulated internal variability would need to be more than twice as large as the most extreme case found in the CMIP5 models, for even the most extreme simulated natural warming event to match the 2016 observed record.
That doesn't mean that the probability is zero. The other issue is the model, and whether it's accurately reproducing the statistical distribution of weather. It's easy to determine if the model is reproducing the mean, because we should know that part of the distribution with a high degree of accuracy. Extreme events, by definition, are rare, and therefore we can't quantify that part of the distribution with as much certainty, and can't know as well whether the model is reproducing those parts of the distribution very well. The actual climate model software is fundamentally no different than weather models, which certainly have biases and other known issues.
I believe the results are still pretty damning, that the events would be extremely unlikely to occur in the absence of anthropogenic forcing. It's still exaggerating to say that the extreme event would be impossible without anthropogenic forcing, and there's no need to make that claim. If the event didn't occur over 5,200 years of a model simulation, and the model didn't even come close to reproducing the event, there are two possibilities that aren't mutually exclusive:
1) The model has issues reproducing extreme events like the one being studied
2) The event would have a much less than 1/5200 probability of occurring in a given year
I suspect the second possibility is probably accurate. It's a damning statement to make without saying the event would have been impossible without anthropogenic forcing. It also forces the deniers to debate the validity of the model (actual science) rather than attacking the credibility of the scientists for not being precise in their statements.
There's a significant problem with the negative feedback you're arguing for. Warming induced by additional carbon dioxide should increase the amount of water vapor in the atmosphere. Water vapor is a far more potent greenhouse gas than carbon dioxide, though with a much lower residence time in the atmosphere than carbon dioxide. Adding water vapor doesn't necessarily mean there are more clouds. If the temperature of the atmosphere increases, more water vapor is needed to reach saturation. Relative humidity is the percentage of the amount of water vapor in the atmosphere at that time relative to the amount of water vapor needed for saturation at the current temperature. The temperature can rise, resulting in more water vapor, yet relative humidity might stay the same or even decrease. That would mean that clouds probably aren't more likely, but the water vapor is still in the atmosphere, acting as a greenhouse gas.
So who do I believe, just about all the scientists in the world, or some assclown who doesn't know the difference between a model and a theory?
Hmmm...tough choice.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
Well this is all very convenient for the alarmists isn't it?
Also in today's news, all opposing viewpoints can now also be blamed ok climate change.
When is the world gonna smarten up and start listening to Slashdot posters and not Oxford scientists when it comes to climate change?
Clearly, it's all gotta be a hoax because it's cold as fuck here right now. And, the smartest man in America told us it was a hoax, so there's that, too.
Yeah it's not like he gets paid to say these things or has any conflict of interest on the issue.
It's nice that they can "NOW" blame disasters on climate change but it isn't like they haven't been doing that for years and even blaming disasters that never happen on climate change.
Al Gore batting a 1000 here
https://wattsupwiththat.com/20...
Oh he isn't a scientist ? Well what about Dr. Hansen
https://wattsupwiththat.com/20...
I don't recall NYC sinking under the waves of a tropical climate New Years.
No, that's not what's being done here and anyone who reads this like that is scientifically illiterate.
The entire 'weather is climate' argument is used by the denialist baffoons to try and discredit the entire concept of climate change. It's essentially saying 'since it happens to be very cold outside the climate cannot be warming.' This is not that in reverse, because the scientists are not trying to prove that the climate is warming by pointing at singular weather events, they don't need to do that because the fact that the global climate is warming has been proven a long time ago by the data and the scientific consensus on the topic is very clear.
They're not claiming that 'weather equals climate', but the entire core of the issue of climate change is that climate affects the weather, that's the whole reason it's a problem. Heating of the entire climate is predicted to increase extreme weather phenomena on both ends of the spectrum (meaning: extreme cold and heat) as well as storms.
It's right there in the damn summary:
No-one's saying that these events were solely caused by global warming but it's pretty clear at this point that the continued warming of the atmosphere is bound to make heat waves and droughts both more common and more severe. Why anyone would think that studying how big of an affect the added energy is having on these events somehow means the experts in the field are 'reversing' the definitions of the term is beyond me.
The reason it's good that this is done is because there exists a misconception both among the general public as well as politicians that climate change is somehow a threat that solely exists in the future. But seeing as how nearly every year in the 2000s so far has broken the record for the hottest year, it's obvious that we're already seeing/feeling the effects of a warming climate, so in my opinion it's very good that this is brought to people's attention so that the sort of 'oh well, we'll deal with the problem later' attitude that some people seem to have can be countered. The problem is already here, and it's already affecting the global populace's health, economy and food production.
On a related note, the talk of climate change 'alarmists' has always seem moronic to me. It's not 'alarmism' to point out facts such as the global average temp is going up year after year, or that there are more and more extreme weather phenomenon. Take an analogy from medicine. Saying you wake up one day with a cough that gets increasingly worse as the days go by, until one day you spike a fever and start coughing blood. You go to the doctor who says they're going to need to do some tests on you, because the symptoms clearly indicate that something is wrong with your body and you may be in danger if that's left unchecked.
If one takes the same attitude in this scenario that many people seem to take towards climate change you'd stand up, laugh, and go 'ahahaha, you're just one of those 'human health alarmists'. Plenty of people have coughed blood and not died, so what do you know? Clearly nothing, so I'm just going to go home."
Now the thing to understand here is that the skeptic maybe right, but we need to consider the game theory of the situation: if your goal is to live longer, then your chances of survival are drastically increased by seeking medical attention, even though it is possible that your body will heal on its own without outside help. Put yourself in this situation and ask, would you rather choose a doctor who wants to ru
"It is the business of the future to be dangerous" -Alfred North Whitehead
TLDR.
This explains why you don't understand anything about climate change, it seems you can't be bothered to read enough to understand. Here's a very simple explanation of both of things you find too incredible to believe:
Extreme cold events can be an effect of climate change because warming in Arctic allows the still very cold air to travel further south by weakening the air currents that used to keep that cold air trapped over the Arctic. It's important to understand that when that cold air escapes from the Arctic, it is replaced by (relatively) warmer air, thus further warming the Arctic, weakening the currents and allowing that cold to escape even further south. Because the escaped polar air also warms at it travels further south, on average, the entire area ends up being warmer than before, even though some areas are much colder than they used to be.
Floods and droughts both being caused by climate change should be obvious. Warm air picks up water from one location (deepening drought) and drops it in another (increasing floods). If you don't understand that, you don't even have a grade 4 level of science knowledge and are completely unqualified to participate in this discussion.
Fanatically anti-fanatical