The Warmer it Grows, the More it Snows

It seems everywhere you turn in the last few weeks, from Minneapolis to Paris, some place somewhere is getting pounded by an unusually strong winter storm. As usual, the under-informed have made it a point to cite these storms as “evidence” against global warming, but as Judah Cohen notes in the New York Times, there is a natural explanation for both the increased temperatures and the record snows:

The high topography of Asia influences the atmosphere in profound ways. The jet stream, a river of fast-flowing air five to seven miles above sea level, bends around Asia’s mountains in a wavelike pattern, much as water in a stream flows around a rock or boulder. The energy from these atmospheric waves, like the energy from a sound wave, propagates both horizontally and vertically.

As global temperatures have warmed and as Arctic sea ice has melted over the past two and a half decades, more moisture has become available to fall as snow over the continents. So the snow cover across Siberia in the fall has steadily increased.

The sun’s energy reflects off the bright white snow and escapes back out to space. As a result, the temperature cools. When snow cover is more abundant in Siberia, it creates an unusually large dome of cold air next to the mountains, and this amplifies the standing waves in the atmosphere, just as a bigger rock in a stream increases the size of the waves of water flowing by.

The increased wave energy in the air spreads both horizontally, around the Northern Hemisphere, and vertically, up into the stratosphere and down toward the earth’s surface. In response, the jet stream, instead of flowing predominantly west to east as usual, meanders more north and south. In winter, this change in flow sends warm air north from the subtropical oceans into Alaska and Greenland, but it also pushes cold air south from the Arctic on the east side of the Rockies. Meanwhile, across Eurasia, cold air from Siberia spills south into East Asia and even southwestward into Europe.

That is why the Eastern United States, Northern Europe and East Asia have experienced extraordinarily snowy and cold winters since the turn of this century. Most forecasts have failed to predict these colder winters, however, because the primary drivers in their models are the oceans, which have been warming even as winters have grown chillier. They have ignored the snow in Siberia.

It goes to show how complex climate is, and it should be interesting to see if climate scientists do indeed start looking more closely at Siberia. In the meantime, I hope Gripweed and the rest of New England stay safe.

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7 Responses to The Warmer it Grows, the More it Snows

  1. Gripweed says:

    I am safe! I had to walk a mile and a half in the road to get to the train, but I made it to work. I think this storm lived up to its billing.

  2. 71LesPaul says:

    Great post. The climate is too complex to accurately model as a means to predict the full impact of climate change, at least for now anyway. Safe to say there are going to be some profound changes in the way the planet deals with all the extra heat and carbon we’ve released.

  3. Drae says:

    LP – thanks. Many of us are already aware how much the jet stream can impact local weather conditions. When we get big troughs in winter, it brings frigid Canadian air, and when the jet stream is north of us, we get mild southern air. Of course, when the jet stream is right over us, we get all the storms.

    And, sadly, I’m going to predict flooding this spring.

  4. 71LesPaul says:

    I think the jet stream is more of an effect than it is a cause of weather patterns. As for your prediction, I’m sure not betting against flooding in the Land of 10,000 Lakes. :-)
    I would fear a long drought and spreading wildfires much more.

  5. Drae says:

    I used to enjoy the MNDoT weather station, with data from all the small airports, and a couple of automated voices. They had maps for everything, including one for the jet stream, and that was the pattern I noticed.

    And Minnesota actually has over 15,000 lakes, but in the springtime that can double if you include very large puddles…

  6. 71LesPaul says:

    There is a pattern between the jet streams and the weather no doubt.

    And I’m not sure how many gazzilions of lakes we have in MI but I know you need a sump pump, a backup sump pump and a backup for the backup.

  7. Drae says:

    And a dehumidifier.

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