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Dumb question but are heat waves like this caused by global warming or are they the result of local weather systems that just happen to line up in a way that re

Dumb question but are heat waves like this caused by global warming or are they the result of local weather systems that just happen to line up in a way that results in especially high temps?

raincom 5y ago
There is a third question, which is mixture of both of your questions: are local weather systems impacted by global warming?
- deleted 5y ago
  [deleted]
- thnujmikkk 5y ago
  Local weather systems are a part of the globe, so yes
nemothekid 5y ago
I don't think heat waves are caused by global warming - I think they happen more often as a result of global warming. For example, a heat wave that would normally happen every once in 100 years now happens once every 10 years.
jandrewrogers 5y ago
Not a dumb question. It is hard to say. There was a similar spate of temperatures a century ago, though this appears to be topping those. Even Seattle, which is robustly protected by its geography, is suffering anomalously high temperatures. Few people have air conditioning because most days rarely exceed 25°C. We are looking at 45°C on Monday, which is a once or twice per century occurrence.
- ehnto 5y ago
  I would love someone more knowledgeable to chime in, but my experience in Australia has taught me that we don't build for long term heat waves. My house can handle a day at 45c, but a week? Everything gets heat soaked, even the cold water tap is hot. Australians rarely have basements, but I wonder if this could be part of the solution long term. I have seen homes in the desert with huge concrete slabs inteded to operate as heatsinks/regulators, perhaps a concrete basement could do the same thing.
  - jandrewrogers 5y ago
    The Pacific Northwest is not built for heatwaves at all. It has a very mild and stable climate as such things go due to the geography. There simply isn't a need to deal with much heat. A serious "heatwave" in Seattle is 30-35°C, and they pass as quickly as they come. Even if homes had a lot of thermal ballast by construction, long runs of high temperatures like now require air conditioning. Something like 25% of homes, mostly newer ones, have air conditioning. It simply has not been needed historically. If there are a few days of 30°C temperatures, you opened a window. This current weather system is running much hotter and much longer than traditional Seattle summer weather.
sephamorr 5y ago
Attribution of weather events is a nontrivial task due to the complexity of weather systems. This is one of the groups that does: https://www.worldweatherattribution.org/ https://www.worldweatherattribution.org/ Tldr, climate change is making many (but not all) of recent extreme weather events more likely or more extreme.
floatingatoll 5y ago
It feels like global warming rotated the microclimate circle that loops around Seattle > Indiana > Arizona > NorCal, about ninety degrees clockwise as a side effect of adding energy into the system. I suspect there’s a better way to say that in jetstream but I neither speak newscaster nor climatologist :( Instead I’ll try to describe what the arrows in that cycle look like to me: The climate spikiness from NorCal wine country moved up to Seattle. The flooding rains moved to Indiana. The endless drought expanded from Arizona to California. And all the weather systems got a jolt of energy, widening the extremes in all locations.
hmottestad 5y ago
Heat waves are weather events, but a general trend of more/longer/warmer heat waves would be considered climate. Global warming is a climate change. Single weather events like a heat wave may very well be the result of global warming, but it could also be a random event. One good example are floods. We usually talk about 5-year, 20-year and 100-year floods. A 100-year flood could be triggered by unusually large snowfall during the winter followed by a particularly wet spring with a sudden heat wave that melts all the snow in mountains at the same time.
- spoonjim 5y ago
  Global warming makes 100-year-floods 10-year-floods.
ajnin 5y ago
Global warming brings more energy into the system so it's likely there will be more wild swings into extreme temperatures in the future and more energetic events like hurricanes etc. (not a climatologist).
DoreenMichele 5y ago
The reality is that we don't actually have the answers people imagine we have. Temperature records have been kept since about the 1850s and data from before that time is based on proxies from which we make inferences. https://en.wikipedia.org/wiki/Global_temperature_record https://en.wikipedia.org/wiki/Global_temperature_record First actual recording of temperature in Seattle, Washington dates to 16 February 1870. https://mrcc.illinois.edu/FORTS/histories/WA_Seattle_Conner.pdf https://mrcc.illinois.edu/FORTS/histories/WA_Seattle_Conner.... I am not readily finding a similar document for Portland, Oregon. In the US, we sometimes have oral histories from Indigenous populations that help clue us. In Southern California, there were Native stories about their ancestors being aware of a lake in what is now the Salton Sea and was dry land when White settlers or explorers were first going into that area. We have data models. We have oral histories. We think we know what the weather was like for thousands of years but actual recorded weather goes back less than two hundred years. So the reality is that we know for certain less than our stories in popular media might lead you to believe. Please keep in mind that our awareness of a hole in the ozone was delayed due to an algorithm that dropped readings of "zero" from the data on the assumption that it was some kind of error. If you think our data models are perfect and humans make no mistakes, you can believe what our news stories tell you. If you don't believe that, then the answer is that "We don't actually know as much as we like to pretend we do." (insert references to The Incredibles and Edna asking "Do you know where he is?" https://www.youtube.com/watch?v=OqMxPw6MVzY https://www.youtube.com/watch?v=OqMxPw6MVzY)
adrianN 5y ago
Here is a graphic that shows the number of days >30°C in Germany over the last few decades: https://twitter.com/DWD_klima/status/1407023635798319106/photo/1 https://twitter.com/DWD_klima/status/1407023635798319106/pho... I think the trend is pretty clear.

Dumb question but are heat waves like this caused by global warming or are they the result of local weather systems that just happen to line up in a way that results in especially high temps?

raincom 5y ago

There is a third question, which is mixture of both of your questions: are local weather systems impacted by global warming?

deleted 5y ago
[deleted]
thnujmikkk 5y ago
Local weather systems are a part of the globe, so yes

nemothekid 5y ago

I don't think heat waves are caused by global warming - I think they happen more often as a result of global warming. For example, a heat wave that would normally happen every once in 100 years now happens once every 10 years.

jandrewrogers 5y ago

Not a dumb question. It is hard to say. There was a similar spate of temperatures a century ago, though this appears to be topping those. Even Seattle, which is robustly protected by its geography, is suffering anomalously high temperatures. Few people have air conditioning because most days rarely exceed 25°C. We are looking at 45°C on Monday, which is a once or twice per century occurrence.

ehnto 5y ago
I would love someone more knowledgeable to chime in, but my experience in Australia has taught me that we don't build for long term heat waves. My house can handle a day at 45c, but a week? Everything gets heat soaked, even the cold water tap is hot. Australians rarely have basements, but I wonder if this could be part of the solution long term. I have seen homes in the desert with huge concrete slabs inteded to operate as heatsinks/regulators, perhaps a concrete basement could do the same thing.
- jandrewrogers 5y ago
  The Pacific Northwest is not built for heatwaves at all. It has a very mild and stable climate as such things go due to the geography. There simply isn't a need to deal with much heat. A serious "heatwave" in Seattle is 30-35°C, and they pass as quickly as they come. Even if homes had a lot of thermal ballast by construction, long runs of high temperatures like now require air conditioning. Something like 25% of homes, mostly newer ones, have air conditioning. It simply has not been needed historically. If there are a few days of 30°C temperatures, you opened a window. This current weather system is running much hotter and much longer than traditional Seattle summer weather.

sephamorr 5y ago

Attribution of weather events is a nontrivial task due to the complexity of weather systems. This is one of the groups that does: https://www.worldweatherattribution.org/ https://www.worldweatherattribution.org/ Tldr, climate change is making many (but not all) of recent extreme weather events more likely or more extreme.

floatingatoll 5y ago

It feels like global warming rotated the microclimate circle that loops around Seattle > Indiana > Arizona > NorCal, about ninety degrees clockwise as a side effect of adding energy into the system. I suspect there’s a better way to say that in jetstream but I neither speak newscaster nor climatologist :( Instead I’ll try to describe what the arrows in that cycle look like to me: The climate spikiness from NorCal wine country moved up to Seattle. The flooding rains moved to Indiana. The endless drought expanded from Arizona to California. And all the weather systems got a jolt of energy, widening the extremes in all locations.

hmottestad 5y ago

Heat waves are weather events, but a general trend of more/longer/warmer heat waves would be considered climate. Global warming is a climate change. Single weather events like a heat wave may very well be the result of global warming, but it could also be a random event. One good example are floods. We usually talk about 5-year, 20-year and 100-year floods. A 100-year flood could be triggered by unusually large snowfall during the winter followed by a particularly wet spring with a sudden heat wave that melts all the snow in mountains at the same time.

spoonjim 5y ago
Global warming makes 100-year-floods 10-year-floods.

ajnin 5y ago

Global warming brings more energy into the system so it's likely there will be more wild swings into extreme temperatures in the future and more energetic events like hurricanes etc. (not a climatologist).

DoreenMichele 5y ago

The reality is that we don't actually have the answers people imagine we have. Temperature records have been kept since about the 1850s and data from before that time is based on proxies from which we make inferences. https://en.wikipedia.org/wiki/Global_temperature_record https://en.wikipedia.org/wiki/Global_temperature_record First actual recording of temperature in Seattle, Washington dates to 16 February 1870. https://mrcc.illinois.edu/FORTS/histories/WA_Seattle_Conner.pdf https://mrcc.illinois.edu/FORTS/histories/WA_Seattle_Conner.... I am not readily finding a similar document for Portland, Oregon. In the US, we sometimes have oral histories from Indigenous populations that help clue us. In Southern California, there were Native stories about their ancestors being aware of a lake in what is now the Salton Sea and was dry land when White settlers or explorers were first going into that area. We have data models. We have oral histories. We think we know what the weather was like for thousands of years but actual recorded weather goes back less than two hundred years. So the reality is that we know for certain less than our stories in popular media might lead you to believe. Please keep in mind that our awareness of a hole in the ozone was delayed due to an algorithm that dropped readings of "zero" from the data on the assumption that it was some kind of error. If you think our data models are perfect and humans make no mistakes, you can believe what our news stories tell you. If you don't believe that, then the answer is that "We don't actually know as much as we like to pretend we do." (insert references to The Incredibles and Edna asking "Do you know where he is?" https://www.youtube.com/watch?v=OqMxPw6MVzY https://www.youtube.com/watch?v=OqMxPw6MVzY)

adrianN 5y ago

Here is a graphic that shows the number of days >30°C in Germany over the last few decades: https://twitter.com/DWD_klima/status/1407023635798319106/photo/1 https://twitter.com/DWD_klima/status/1407023635798319106/pho... I think the trend is pretty clear.