6 ms·

Europe sees warmest winter since records began

62 points by reddotX 7y ago

chrisco255 7y ago
Can anyone explain how the Northern Hemisphere has snow mass more than two standard deviations above median this winter, despite the local warming in Europe? https://globalcryospherewatch.org/state_of_cryo/snow/fmi_swe_tracker.jpg https://globalcryospherewatch.org/state_of_cryo/snow/fmi_swe...
- ajuc 7y ago
  More snow falls just below 0C than in -10C or -20C because air can hold more water vapor the warmer it is. If it's -20C the water from the ground doesn't go into the air as much and doesn't fall back as a snow.
  - chrisco255 7y ago
    Snow forms in the upper atmosphere at about 15,000 feet before it falls to the ground. Temperatures are always about 25C less there than on the ground. It's not strictly true that cold air holds less water vapor. Water vapor is more likely to condense at cooler temps. The likelihood that water will condense to form rain and snow droplets is impacted by the dew point and the amount of particles in the atmosphere to formulate liquid or ice.
  - usr1106 7y ago
    Yes, and it's snow mass. If you do manual snow removal in your yard at 0°C or -5°C you feel a huge difference. And even if the mass is there, it melts earlier.
- Stevvo 7y ago
  It's odd, I'm in the Alps. It snowed twice in all of February. Since the beginning of March, we've averaged more than a foot of snow fall a day. The article only counts to the end of February. Feels like winter is back.
- xaedes 7y ago
  I dont know, but the last glacial periods started after rapid (in geological terms, still long times) increases of temperature. Followed by declining temperature and increasing ice volume over thousands of years. https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png
jsnider3 7y ago
Have we considered doing something about global warming?
- toron123 7y ago
  Europe is doing quite a lot compared to others, especially China, USA and India.
  - MrDresden 7y ago
    Perhaps, but so much more needs to be done. I am afraid that we as a species wont be able to act together quickly enough to have a real chance of halting the run-away changes that seem to be starting up all over the planet.
    - tcd 7y ago
      I think it's already too late - US is withdrawing from the Paris agreement. Australia is in complete denial it seems We need to reduce emissions yesterday and reduce our plastic output considerably. We're not doing anything on a scale big/quick enough to matter. We don't have until 2050 or the targets some governments have set. We need it done by next year, 2021, but that's unlikely to happen. We need new laws enacting tomorrow and to give everyone a big kick up the ass to get their acts together. That's not going to happen, no matter how desperate Greta, Attenborough make it seem.
      - perfunctory 7y ago
        > That's not going to happen, no matter how desperate Greta, Attenborough make it seem. True. Greta alone won't save the climate for us. We need to get afk and go help her.
    - perfunctory 7y ago
      > I am afraid that we as a species wont be able to act together quickly enough Let me just point out that we the species also include you. And me. It's up to us.
bsaul 7y ago
from post "1924-25 was similarly warm, with a couple of degrees above the climate at that time" so was it or was it not the warmest since records began ( and by how much) ? i don't get it..
- inimino 7y ago
  It was, by 1.4 degrees. 1924-25 was similarly warmer than the baseline at that time. The article describes an above-average year on top of a warming trend.
- myrion 7y ago
  It was the warmest since records began. '24-'25 was just similarly much warmer than average at that time. Winters that are 3-4 degrees above average happen every so often. However, since the average is now much higher than a hundred years ago, it was still much warmer than back then.
- morelisp 7y ago
  1924-25 was above average for its period. 2019-20 is similarly above average for its period, and the average for its period is higher.
pgillc 7y ago
I tried hard to resist how unusually warm March (and February) has felt.
perfunctory 7y ago
In case somebody is wondering about the significance of a temperature record https://books.google.com/books?id=N0FLSOmeFPsC&pg=PT59 https://books.google.com/books?id=N0FLSOmeFPsC&pg=PT59 Bottom line: records are extremely rare if events occur at random. If new records become far more common than the harmonic series predicts, then this is telling us that annual climatic events are no longer independent annual events but are beginning to form part of a systematic non-random trend.
Claudus 7y ago
They did just switch from ERA-Interim to ERA5 data source, April 2019. https://climate.copernicus.eu/era5-new-dataset-monthly-climate-bulletin https://climate.copernicus.eu/era5-new-dataset-monthly-clima...

62 points by reddotX 7y ago

Can anyone explain how the Northern Hemisphere has snow mass more than two standard deviations above median this winter, despite the local warming in Europe? https://globalcryospherewatch.org/state_of_cryo/snow/fmi_swe_tracker.jpg https://globalcryospherewatch.org/state_of_cryo/snow/fmi_swe...

ajuc 7y ago
More snow falls just below 0C than in -10C or -20C because air can hold more water vapor the warmer it is. If it's -20C the water from the ground doesn't go into the air as much and doesn't fall back as a snow.
- chrisco255 7y ago
  Snow forms in the upper atmosphere at about 15,000 feet before it falls to the ground. Temperatures are always about 25C less there than on the ground. It's not strictly true that cold air holds less water vapor. Water vapor is more likely to condense at cooler temps. The likelihood that water will condense to form rain and snow droplets is impacted by the dew point and the amount of particles in the atmosphere to formulate liquid or ice.
- usr1106 7y ago
  Yes, and it's snow mass. If you do manual snow removal in your yard at 0°C or -5°C you feel a huge difference. And even if the mass is there, it melts earlier.
Stevvo 7y ago
It's odd, I'm in the Alps. It snowed twice in all of February. Since the beginning of March, we've averaged more than a foot of snow fall a day. The article only counts to the end of February. Feels like winter is back.
xaedes 7y ago
I dont know, but the last glacial periods started after rapid (in geological terms, still long times) increases of temperature. Followed by declining temperature and increasing ice volume over thousands of years. https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png https://en.wikipedia.org/wiki/File:Ice_Age_Temperature.png

jsnider3 7y ago

Have we considered doing something about global warming?

toron123 7y ago
Europe is doing quite a lot compared to others, especially China, USA and India.
- MrDresden 7y ago
  Perhaps, but so much more needs to be done. I am afraid that we as a species wont be able to act together quickly enough to have a real chance of halting the run-away changes that seem to be starting up all over the planet.
  - tcd 7y ago
    I think it's already too late - US is withdrawing from the Paris agreement. Australia is in complete denial it seems We need to reduce emissions yesterday and reduce our plastic output considerably. We're not doing anything on a scale big/quick enough to matter. We don't have until 2050 or the targets some governments have set. We need it done by next year, 2021, but that's unlikely to happen. We need new laws enacting tomorrow and to give everyone a big kick up the ass to get their acts together. That's not going to happen, no matter how desperate Greta, Attenborough make it seem.
    - perfunctory 7y ago
      > That's not going to happen, no matter how desperate Greta, Attenborough make it seem. True. Greta alone won't save the climate for us. We need to get afk and go help her.
  - perfunctory 7y ago
    > I am afraid that we as a species wont be able to act together quickly enough Let me just point out that we the species also include you. And me. It's up to us.

bsaul 7y ago

from post "1924-25 was similarly warm, with a couple of degrees above the climate at that time" so was it or was it not the warmest since records began ( and by how much) ? i don't get it..

inimino 7y ago
It was, by 1.4 degrees. 1924-25 was similarly warmer than the baseline at that time. The article describes an above-average year on top of a warming trend.
myrion 7y ago
It was the warmest since records began. '24-'25 was just similarly much warmer than average at that time. Winters that are 3-4 degrees above average happen every so often. However, since the average is now much higher than a hundred years ago, it was still much warmer than back then.
morelisp 7y ago
1924-25 was above average for its period. 2019-20 is similarly above average for its period, and the average for its period is higher.

pgillc 7y ago

I tried hard to resist how unusually warm March (and February) has felt.

perfunctory 7y ago

In case somebody is wondering about the significance of a temperature record https://books.google.com/books?id=N0FLSOmeFPsC&pg=PT59 https://books.google.com/books?id=N0FLSOmeFPsC&pg=PT59 Bottom line: records are extremely rare if events occur at random. If new records become far more common than the harmonic series predicts, then this is telling us that annual climatic events are no longer independent annual events but are beginning to form part of a systematic non-random trend.

Claudus 7y ago

They did just switch from ERA-Interim to ERA5 data source, April 2019. https://climate.copernicus.eu/era5-new-dataset-monthly-climate-bulletin https://climate.copernicus.eu/era5-new-dataset-monthly-clima...