12 ms·

One of the things about "extreme weather attribution" that makes me uncomfortable is the asymmetry of it. To be clear: I'm in no way an expert (or even educate

• divbzero 5y ago
  Extreme weather can occur in both directions. A year with more rain may be less prone to fire but more prone to flooding. It also does not take natural disaster to notice extremes. People who have lived in the same area awhile will know if there is an unusually wet, dry, hot, or cold year.
  • jjulius 5y ago
    >... more prone to flooding. Or mudslides.
  • timmg 5y ago
    > Extreme weather can occur in both directions. Of course that's true. What I guess I was trying to say is that a change in climate doesn't necessarily mean more extreme weather (in every instance, I mean). A change in climate could cause something to happen more or happen less. But no one is going to study a given year and a given place that doesn't have an extreme weather event.
    • hedgehog 5y ago
      Discrete events are a human construct but the underlying data is continuous. I'm not sure the attribution of individual events is that meaningful and the article suggests for a variety of reasons the models aren't really built for that purpose anyway. So I think in a sense you are right, but this doesn't necessarily imply any problem for the predictive value of the models or research going into them.
    • ruined 5y ago
      one thing to note is that, generally, any comparatively calmer system with fewer extreme events is in a lower energy state. and that is exactly what we are moving away from.
  • godelski 5y ago
    Actually it even gets more complicated. California is a good example. Dry weather makes more fires yes. More fires means less vegetation with deep roots. Not only do these shrubs burn more easily, but they neither hold back water. This makes heavy rainfall more dangerous as flash floods become more common. It's crazy how interconnected these things are and frustrating because it becomes difficult to talk about. The whole picture is so complicated but focusing on a small aspect over simplifies the problem too much.
    • Breazy 5y ago
      The wetter weather enjoyed by the past few generations of Californians was an aberration. California is usually even dryer than it is presently. > Paleoclimatological studies indicate that the last 150 years of California's history have been unusually wet compared to the previous 2000 years. Tree stumps found at the bottom of lakes and rivers in California indicate that many water features dried up during historical dry periods, allowing trees to grow there while the water was absent. These dry periods were associated with warm periods in Earth's history. During the Medieval Warm Period, there were at least two century-long megadroughts with only 60-70% of modern precipitation levels. Paleoclimatologists believe that higher temperatures due to global warming may cause California to enter another dry period, with significantly lower precipitation and snowpack levels than observed over the last 150 years.[7] https://en.wikipedia.org/wiki/Climate_change_in_California#Paleoclimatological_evidence https://en.wikipedia.org/wiki/Climate_change_in_California#P...
  • prawn 5y ago
    Might be wrong, but I think unseasonably wet weather can also increase the fuel load for a fire. i.e., boisterous undergrowth due to wet weather during Spring, which then dries out and is available for fire season.
  • redisman 5y ago
    Washington has also had unusually wet years that encourage more growth on the forest floor so there is more fuel by the time the 3 month dry and hot season rolls over
• dv_dt 5y ago
  Climate change means you can have an extreme drought, followed by a fire, followed by extreme rain then mudslides.
  • hackeraccount 5y ago
    Doesn't that seem wrong on some level? It's like saying climate change will make weather "worse" which seems too anthropocentric.
• contravariant 5y ago
  That's why in these discussions it's usually better to talk about specific statistics like 'the chance of a wildfire has gone up by 20%', or perhaps more clearly 'the average time between extreme floods has gone down from once every 100 years to once every 60' (which I find communicates the point a bit more clearly). That said personally I think that should be as far as the discussion goes, talking about a specific event and asking whether it's because of climate change is silly and leads to counter intuitive results because by nature extreme weather events are mostly caused by bad luck. Climate changes the frequency of extreme events, but talking about the frequency of a singular specific event is impossible. And talking about just 1 or 2 of them isn't quite enough either, events will occur at a rate far above or below that predicted by the best weather models simply because of (bad) luck. I sometimes get the feeling that people try to attribute extreme weather to climate change because it improves the narrative, or as proof that climate change has happened. But personally I find this a bit silly since the fact that the global average temperature has increased and the effects this has on weather shouldn't be all that controversial.
  • kkylin 5y ago
    Absolutely agree with all this. I'd also want to add that another thing to think about is not just how unlikely any particular event is, but the probability of multiple unlikely events occurring across the globe in a relatively short time. After all, Earth is big enough that rare events will happen somewhere. Unusual weather patterns in multiple locations start to point to a systematic cause.
  • dpierce9 5y ago
    Replace ‘extreme weather’ with ‘lung cancer’ and ‘climate change’ with ‘smoking’ to see the soundness of this reasoning.
    • sanxiyn 5y ago
      Lung cancer risk was established with control group. We don't have control group for a planet so we use climate models. The article is about remembering that we use models because of lack of alternatives, not because they are as good as control group.
• throwJan22 5y ago
• vkou 5y ago
  This year, the pacific north west got hit with the four Fs. Fires, floods, and fucking freezing weather. In the summer, we had an unprecedented heat wave which killed thousands of people. Seattle hit 108°F/42°C. The town of Lytton, BC, hit 118°F/48°C[0], and then completely burnt down in a 30 minute firestorm. More rain would have been great. We didn't get it. We got it in the winter, and it was absolutely devastating. [1] To cap the year off, we ended with a record-setting freeze (With, thankfully, comparatively moderate snowfalls). So, yes, more rain, less rain, more heat, less heat, we got all that. Unfortunately, weather is not a bank account, and having your town burn down to the ground in the summer, followed by a flood in the winter doesn't tend to cancel things out. [0] An all-time heat record for Canada. [1] https://en.wikipedia.org/wiki/November_2021_Pacific_Northwest_floods https://en.wikipedia.org/wiki/November_2021_Pacific_Northwes...
  • deleted 5y ago
    [deleted]
• SV_BubbleTime 5y ago
  > No one is going to bother doing an attribution study to say, "Climate change is 20% responsible for the fact that we didn't have a fire this year." Well, I mean you would hope so since that would be honest science.
• foxes 5y ago
  This comment reads more like dismissive pedantry. What happens on the whole statistically matters more than hoping to get lucky with perhaps some local effects cancelling each other out. What is your actual point?
  • xyzzyz 5y ago
    The point here is that "local effects cancelling each outer out" sum up to what happens statistically on the whole. You need to account for all of these.
• notatoad 5y ago
  "a fire this year" is a really vague and imprecise way to measure things, and leads to trying to conclude weird things like whether or not a quiet fire season was caused by climate change. that's why scientists don't measure things that way. the more precise way to measure would be to increase the sample size by counting a precise metric like total acres burned per season, and measuring it over a longer period of time to determine whether or not forest fires are generally getting worse or not. and if they're getting worse, how much are they getting worse by, and how much of that trend can be attributed to climate change.
• photochemsyn 5y ago
  Extreme weather generally involves intersecting weather systems. For example, 'The Perfect Storm' of movie fame was the intersection of the remnants of a hurricane coming up from Gulf of Mexico with a polar cold front coming across Canada and as I recall a low pressure system out around Nova Scotia. The timing of these events was basically random; if the events had been staggered a few days apart instead of hitting at the same time, it wouldn't have been a perfect storm. So, where models predict an increase in such events comes down to increasing probabilities of the individual events, kind of like throwing the dice twice as often as before, then you're going to get double sixes (i.e. extreme events) more frequently. As far as the attribution of specific events, well, you can look back in history and say, historically we've had these events every 100 years or so, so we shouldn't expect three such events over a twenty-year period. This is similar to how a casino might suspect a player is using a loaded die. However, for one specific event, is it possible? Plausibly you can examine the details of a single event and ask, okay, are there physical characteristics here directly related to climate change, in the same way one could examine a die to see if it was really symmetrical or not? One could perhaps use expectation results, i.e. "we expected this kind of extreme weather event to occur with greater frequency outside the regions where they normally take place, according to frequency results in models forced with extra CO2" etc. Really though, it's when you get 500-year floods every 5-10 years in Europe, then you know you're 'testing the historical limits'.
• YZF 5y ago
  I think you're mostly correct. And this is a problem with the idea of trying to model for this given all the variables and outcomes. Climate change should be as simple as: 1) we have pretty decent models and data that show that man is having a considerable impact on weather/climate. 2) we live in a fragile system and are fragile creatures, between us and mother nature we lose every single time, and we lose big, 3) do you really want to find out where this ends? I think most people just look around and see that things are changing. The attribution studies are sort of a moot point. It's the actual change that is going to make us act. Already is, a little. Nobody is going to understand all the weaseling around this could have occurred by chance but we think it's more likely to occur because we modeled it but our models can't predict those low frequency really severe events so we've modeled less severe events and are guessing. If we do start seeing more and more serious weather events (like we seem to be) there's going to be some drastic action (too late?) and if we won't then I guess we're ok by some luck.
• samstave 5y ago
  I've always wondered why we don't exploit gaming. --- Build a SIMCITY and use the ACTUAL policies and everything from actual cities... including infrastructure and have people game the city... Have AIs do so as well... billions of times - and implement best options.... Develop the game such that one person could only focus on finance, or infra, or transit... Wow this game exists!?? and its called .gov but its running on windows 3.11 in my garage? How fix?
• UncleMeat 5y ago
  > No one is going to bother doing an attribution study to say, "Climate change is 20% responsible for the fact that we didn't have a fire this year." This is not true. In fact, I'm aware of several papers that have made an argument that climate change will lead to more rain in California. They don't appear to be winning the argument but for many years this was a contentious discussion among atmospheric scientists. Academics absolutely do the research you are describing. Would those papers make their way to mass media or social media discussions? Probably less so. But they are there amongst the communities that matter most in the conversation.