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Having studied some meteorology in college I haven't heard a coherent example of what changes people believe have happened to the weather patterns or why. If yo

by mentat 11y ago

Having studied some meteorology in college I haven't heard a coherent example of what changes people believe have happened to the weather patterns or why. If you want to reply here, I'll check back from time to time.

thaumaturgy 11y ago
> Having studied some meteorology in college Ah, in that case, here's my understanding, in brief. There are several components: 1. California has had multi-hundred-year drought cycles in the past, according to tree ring data, and the last several hundred years have been unusually wet by comparison. It's possible that we're re-entering a long period of overall drought. (e.g. http://www.nytimes.com/2015/04/14/science/californias-history-of-drought-repeats.html?_r=0 http://www.nytimes.com/2015/04/14/science/californias-histor...) 2. The current drought has been exacerbated primarily by a pattern of high and low pressure systems over the arctic, the polar vortex system. The newer "curvy" shape of the polar vortex is leading to systems which are keeping cold fronts from descending into the west coast. 3. The current working theory is that the shape of the polar vortex is influenced mostly by the temperature of the arctic, so it's not likely to return to what we thought of as normal until the arctic starts to cool down again, which might not be happening anytime soon. (e.g. https://en.wikipedia.org/wiki/Polar_vortex#Climate_change https://en.wikipedia.org/wiki/Polar_vortex#Climate_change -- sorry for Wikipedia link.) 4. There has been a gradual decrease in snowfall over the Rockies and, I think, the Cascades region. (e.g. https://www.ncdc.noaa.gov/sotc/drought/201502 https://www.ncdc.noaa.gov/sotc/drought/201502, http://usatoday30.usatoday.com/weather/news/2011-06-10-climate-change-global-warming-rockies-snow_n.htm http://usatoday30.usatoday.com/weather/news/2011-06-10-clima...) A lab in Berkeley is responsible for measuring snow pack in the Sierra, and they have some data going back to the late 19th century. Unfortunately, all I can find are graphs of their data, not their actual data, so I have to contact them and see if they're willing to share that so I can see how the average is changing. My hunch -- although it's only a hunch at this point -- is that I'll find a slight overall decline in average snowfall, same as there is in the Rockies and Cascades. Seeing if this data is available is part of what's holding up a more comprehensive reply. I have links to articles for most (all?) of this, but ... it's a little bit discombobulated still. I think it really needs to be presented more coherently to look very convincing. Part of the reason that I'm reluctant to start sharing links right away is that some of the sources I have at the moment are crappy little blogs -- thank you very much Google -- and I have to take the graphs they've ripped off and try to locate the primary sources they ripped them off from and then read them and make sure the context is correct and all that. I'm not a meteorologist or climate scientist, it's likely there are areas that I'm oversimplifying or misunderstanding. But, I am an avid reader, and I haven't come across much material that's painting an optimistic view of California's climate in the near future.

by mentat 11y ago

thaumaturgy 11y ago

> Having studied some meteorology in college Ah, in that case, here's my understanding, in brief. There are several components: 1. California has had multi-hundred-year drought cycles in the past, according to tree ring data, and the last several hundred years have been unusually wet by comparison. It's possible that we're re-entering a long period of overall drought. (e.g. http://www.nytimes.com/2015/04/14/science/californias-history-of-drought-repeats.html?_r=0 http://www.nytimes.com/2015/04/14/science/californias-histor...) 2. The current drought has been exacerbated primarily by a pattern of high and low pressure systems over the arctic, the polar vortex system. The newer "curvy" shape of the polar vortex is leading to systems which are keeping cold fronts from descending into the west coast. 3. The current working theory is that the shape of the polar vortex is influenced mostly by the temperature of the arctic, so it's not likely to return to what we thought of as normal until the arctic starts to cool down again, which might not be happening anytime soon. (e.g. https://en.wikipedia.org/wiki/Polar_vortex#Climate_change https://en.wikipedia.org/wiki/Polar_vortex#Climate_change -- sorry for Wikipedia link.) 4. There has been a gradual decrease in snowfall over the Rockies and, I think, the Cascades region. (e.g. https://www.ncdc.noaa.gov/sotc/drought/201502 https://www.ncdc.noaa.gov/sotc/drought/201502, http://usatoday30.usatoday.com/weather/news/2011-06-10-climate-change-global-warming-rockies-snow_n.htm http://usatoday30.usatoday.com/weather/news/2011-06-10-clima...) A lab in Berkeley is responsible for measuring snow pack in the Sierra, and they have some data going back to the late 19th century. Unfortunately, all I can find are graphs of their data, not their actual data, so I have to contact them and see if they're willing to share that so I can see how the average is changing. My hunch -- although it's only a hunch at this point -- is that I'll find a slight overall decline in average snowfall, same as there is in the Rockies and Cascades. Seeing if this data is available is part of what's holding up a more comprehensive reply. I have links to articles for most (all?) of this, but ... it's a little bit discombobulated still. I think it really needs to be presented more coherently to look very convincing. Part of the reason that I'm reluctant to start sharing links right away is that some of the sources I have at the moment are crappy little blogs -- thank you very much Google -- and I have to take the graphs they've ripped off and try to locate the primary sources they ripped them off from and then read them and make sure the context is correct and all that. I'm not a meteorologist or climate scientist, it's likely there are areas that I'm oversimplifying or misunderstanding. But, I am an avid reader, and I haven't come across much material that's painting an optimistic view of California's climate in the near future.