Northeast Snowstorms & Atlantic Water Vapor: No Connection in Last 27 Years

January 30th, 2015 by Roy W. Spencer, Ph. D.

One of the theories of how snowstorms can be made worse is that warming oceans provide more moisture for fuel.

While the theory sounds logical and even attractive, there are many ingredients that go into snowstorm formation. There has to be a synoptic scale disturbance feeding off the temperature contrast between the land and ocean, and since the land-ocean temperature contrast has actually DECREASED in the last several decades (if you believe the thermometer data), this would reduce the energy available for storm formation. (The “more-wavy” jet stream theory is highly suspect…without a greater temperature contrast, there is not as much thermal energy available for “baroclinic instability”).

Nevertheless, there do seem to have been more snowstorms in the Northeast U.S. in the last decade, so what might be the cause? As a meteorologist, my first inclination is to blame, in effect, “chaos”. Weather and climate variations are chaotic, there ARE weather patterns that can get set up and then persist. But these regional influences are basically disconnected from whether the global average temperature happens to be 1 deg. warmer or cooler. They are instead being driven by temperature contrasts of many tens of degrees.

But we can examine with observational data Kevin Trenberth’s hypothesis that increased Northeast snowstorms are the result of more water vapor from the North Atlantic.

For the last 27 years we have had the SSM/I and SSMIS instruments monitoring total water vapor content over the oceans every day. I took the Northwest Atlantic area from 30N to 50N, and 50W to 80W and examined the monthly average water vapor over this area versus the NESIS (Northeast Snowfall Impact Scale) index.

The results suggest basically no relationship between available water vapor and snowstorm events over the last 27 years:

There is little if any  relationship between Northeast U.S. snowstorms and atmospheric water vapor over the Northwest Atlantic between 1988-2014.

There is little if any relationship between Northeast U.S. snowstorms and atmospheric water vapor over the Northwest Atlantic between 1988-2014.

In fact, while warm season water vapor has increased, cold season water vapor (if anything) has decreased on average over the region, making less vapor available for storms. The net trend through all seasons is about +0.5% per decade over the 27 year period.

There is always abundant water vapor available for U.S. snowstorms to feed off of, just as there is always abundant tropical water vapor available for hurricanes and typhoons. But that’s not the limiting factor in storm formation. What is necessary is the variety of conditions which can support the formation of low pressure centers….sufficient water vapor is usually ready and waiting to play its part.

It has more to do with the necessary temperature contrast between air masses (and in the case of tropical cyclones, vertical wind shear). And since global warming (no matter the cause) will lead to the continents warming faster than the ocean (reducing the energy for incipient storms), there is no convincing way to blame global warming for increasing snowstorm activity in the Northeast U.S.


27 Responses to “Northeast Snowstorms & Atlantic Water Vapor: No Connection in Last 27 Years”

Toggle Trackbacks

  1. jimc says:

    One obvious observation from the moisture trend lines is that December’s moisture has been steadily increasing (’88 to ’14 anyway) while February’s has been decreasing. No idea what that means, if anything. Does it fit with any of the oscillations?

  2. Norman says:

    Dr. Spencer

    “(The “more-wavy” jet stream theory is highly suspect…without a greater temperature contrast, there is not as much thermal energy available for “baroclinic instability”).”

    I really do not know how they came up with that one. All material about Rossby waves (I could find)state their amplitude is greatest in the winter months (in Northern Hemisphere) when the temperature gradient between poles and tropics is the greatest. I did have one college class in meteorology and I still cannot understand how this theory is being pushed by the likes of an established science magazine like Scientific American. Where are all the meteorologists when they come up with these ideas?

  3. jimc says:

    Some University of Toronto physicists weigh in on the subject using a heat engine analogy:
    “Global warming won’t mean more stormy weather”
    http://phys.org/news/2015-01-global-wont-stormy-weather.html

  4. John F. Hultquist says:

    The jet streams motions are influenced by Earth’s rotation and the formation is close to the Tropopause. There is a major and sustained uplift of air in the Equatorial region while in the higher latitudes – where that now cooled air descends – there is less space (volume in the atmosphere; area on the surface). Same amount of air into a smaller space means the rate of flow has to be faster. The idea of catastrophic anthropogenic global warming (CAGW) is based on a closer to the surface set of phenomena – shortwave to longwave conversion, absorption and radiation – where the CO2 and other radiatively active gases are produced and are concentrated.
    Assuming the above is reasonably correct, I too find the more-wavy jet stream theory highly suspect.

    As for snow (just east of the Cascades in Washington State) in the winter of ’96 we got 5 feet or about 5X the average. This winter – almost none.

  5. ren says:

    The lowest pressure in the lower stratosphere is currently on the north-eastern Canada.
    http://www.geomag.nrcan.gc.ca/images/field/fnor.gif

  6. “Kevin Trenberth’s hypothesis”

    Trenberth doesn’t present his claims as a hypothesis but as a statement of fact. A quote from a recent media interview:

    “At present sea surface temperatures are more the 2F above normal over huge expanses (1000 miles) off the east coast and water vapor in the atmosphere is about 10% higher as a result. About half of this can be attributed to climate change.”

    There are two possibilities here. The guy was misrepresented in the interview, or he has moved from science to crankism.

    • An Inquirer says:

      From 2011 to 2013, the CAGW proponents claimed that snow in Florida and record snowfall in the south were due to increased atmospheric water vapor which was due to higher ocean temperatures. But the moisture-providing ocean areas for these snow events came from the Gulf and the Atlantic which had temperatures BELOW historic averages. When California had its last season of plentiful precipitation, the Pacific Ocean had temperatures BELOW historic averages. The reason for the snow was cold atmospheric temperatures — along with the weather conditions described by Dr. Spencer. Meanwhile, the severe drought in CA continues despite Pacific Ocean temperatures that have persisted above normal for months.

  7. Alan says:

    “there is no convincing way to blame global warming for increasing snowstorm activity in the Northeast U.S.”

    The ‘convincing’ occurs when the story is fed to the media which repeats the claim again and again, ad nauseum, until the public accepts it as fact. Once this occurs, the science is settled! 😉

  8. Bob Weber says:

    I was astounded that Kevin T would make such an obtuse statement, essentially blaming the blizzard on ‘man-made climate change’, as though that is a separately identifiable force that can be measured against and discerned from natural variability (which includes solar variability).

    The MET office recently declared that the 2014 “record” temps were caused by high SSTs on the US coasts (and SE Asia) late in the year. I agree with that, but not the attribution to CO2. It was the Sun.

    SSTs in late 2014 to now have been higher due to the recent high solar activity from the last peak(s) of SC24, going into late 2014, that added more heat into the top layers of the ocean. Solar cycle 24 “peaking” looks to be done, and as such, I do not expect higher SSTs again until the next solar cycle maximum, if not later, perhaps into SC26, depending on the strength of SC25.

    Very soon, I will be releasing my solar supersensitivity accumulation model that explains the rise and fall of SSTs since 1850 as resulting from the rise and fall of solar activity, using F10.7cm solar flux back to 1947, where on average the oceans accumulate heat above ~120 sfu (+/- a few solar flux units), and release it below that threshold. Before 1947 I use SSNs.

    Key to understanding the solar-SST link are new findings last year regarding the timing of Northeast Pacific SST and SLP response wrt to higher solar activity. We saw in 2014 an average solar flux of 146 sfu/day, pushing SSTs high on the N American coasts, especially late in the year, when since mid-Nov to the end of Dec, solar flux averaged 163 sfu/day. Keep in mind that the daily average F10.7 flux since the end of the solar modern maximum in 2003 to now has been a measly 100 sfu, which is the one true cause of the “pause”.

    ** The cause of the pause was the cause before the pause. **

    People did not cause SSTs to go up in 2014 or any other time via CO2 emissions, the Sun caused it!

    The weak “blizzard” (it was nothing special in my book) on the NE coast was caused by the clash of moist warm air (water vapor) driven by solar warming in 2014, and the cold arctic air riding the windy edge of the Rossby wave along the offset polar vortex, caused by a solar-induced SSW event Jan 6/7.

    See the SSWs here http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/02mb9065.gif

    The Sudden Stratospheric Warming (SSW) event on Jan6/7 that displaced the polar vortex was the first major “electric weather” event of 2015, and was caused by a high density solar sector boundary crossing (SSBC) that had maximam impact at 0900UTC Jan 6. The big 24nT impact, which lasted for several hours, caused a huge spike in hemispheric power, 4X background.

    The IMF Bz flipped from 10nT positive to negative 24nT very quickly as the boundary edge passed by the Earth, causing major electron precipitation, a big 3% daily drop in Oulu cosmic ray intensity, warmed the stratospheric ozone just south of Greenland (which is why it’s called a SSW), expanding the atmosphere at those heights, making waves that caused the polar vortex to shift. Spaceweather.com called it an “unexpected G3-class geomagnetic storm”; the next day they featured a story about how it caused “beautiful aurora in Russia” that night. Kp went up to 6 by 0900UTC and then up to 7 by 1200UTC.

    On Jan 7 US temps were already feeling the effects of the earlier Dec 23 SSW event, caused by an even bigger near 40nT IMF spike, as US windspeeds on Jan 7 were 35-40MPH across the eastern half of the US, wind chills were in the twenties as far south as Texas, and the southern front of the Rossby Wave was all the way down to the Gulf Coast.

    It’s always the same mechanisms over and over, well illustrating the time-dependent and layered solar weather effects on the Earth: one effect being warming, the other effect cooling, and the clash of the two effects causes many “Extreme weather events”.

    That’s why people are talking about a “wavy” jetstream. It moves in response to solar activity & cosmic ray modulation.

    Ren, bless his heart, has been trying for some time to get people to focus on the solar-cooling effect, just as I have been focusing since last year on the solar-warming effect on the weather and climate. Too bad English isn’t ren’s primary language, as I’m sure his explanations would be more apparent to many by now.

    I rank Kevin T right down there with that dolt from NASA, Gavin Schmidt, in terms of their lack of understanding objective reality.

  9. Chad Jessup says:

    I would say any increase of snow storms in New England would result from a greater temperature gradient between the Arctic and the equator, thus allowing the lower pressure moisture laden equatorial air to travel north, in the process dropping precipitation over that area.

    The North Atlantic hardly factors in to that situation.

  10. Thanks, Dr. Spencer.
    “What is necessary is the variety of conditions which can support the formation of low pressure centers…. sufficient water vapor is usually ready and waiting to play its part.”
    This is obvious to a meteorologist, but apparently not for a climatologist. Sad.

  11. Ulric Lyons says:

    On the water vapour issue, I would have thought that what matters is the wind direction that day, and whether there was an onshore moisture contribution or not, rather than what the average for the month was.
    Many of these Northeasters seem to have a similar pattern, occuring during a shift to a positive Arctic Oscillation, after a period of negative AO.
    I have for a number of years been producing solar based long range forecasts for AO/NAO states at down to daily scales, so I cannot regard them as being chaotic. From my frame of reference, the prerequisite for such events is firstly a negative AO from a weaker short term solar signal, which is the antithesis of the theoretical effect of increased GHG forcing on the AO.

  12. James M. Davidson says:

    Never mind “percent departure from average.” From more than 2,000 weather stations world wide balloons have been launched twice a day, usually at mid-day and midnight, since 1949. The balloons carry an instrument package to measure air temperature, air temperature and relative humidity. These measurements are transmitted to the ground station by radio, and, in modern packages, the measurements go straight into a computer. The balloons ascend to between 100,000 and 120,000 feet where the balloon bursts in the decreased air pressure, and the instrument package returns to earth on a small parachute. Two flights a day, every day, from 2,000 stations since 1949. Thats a LOT of data. This data is archived in France and shows a DECREASE in relative humidity at all pressure altitudes since 1949, the exact opposite of the hypothesis ” more CO2 warms the atmosphere and results in more water vapour.” ( Don’t you hate when that happens?) There is nothing worse, on this earth, than to watch a beautiful hypothesis being destroyed by a single ugly fact.

  13. sky says:

    Inasmuch as the North Atlantic is downstream, there should little expectation that Atlantic water vapor would influence snowfall in the Eastern US seaboard. The more telling analysis would involve Gulf of Mexico water vapor.

  14. MojoMojo says:

    http://www.washingtonpost.com/news/energy-environment/wp/2015/02/10/what-the-massive-snowfall-in-boston-tells-us-about-global-warming/

    ” “Sea surface temperatures off the coast of New England right now are at record levels, 11.5C (21F) warmer than normal in some locations,” says Penn State climate researcher Michael Mann.”

  15. tonyon says:

    …global warming (“good” no longer spend cold)… the discharge of pollutants into the air with its greenhouse effect is melting the Poles. This large amount of freshwater to the ocean could stop deep sea currents which depend on a delicate balance between fresh and salty water and temperatures. Heat from the Sun reaches Ecuador and currents distribute it throughout the Planet, then…goodbye to our warm climate. The horizontal oceanic currents produced by winds and some others by the rotation of the Earth, rotating all by the Coriolis effect, will continue…but the vertical currents produced by the sinking of horizontal currents of dense salty water that reaches the Poles where the water is sweeter, and form deep currents would stop (why are the Grand Banks fishing in cold latitudes?…because over there is the polar ice, freshwater, different sweet/salty density, salty dense water arriving and sinks in a freshwater environment, nutrients that are removed from the bottom and rise to the surface, phytoplankton that feed on nutrients, zooplankton that feed on phytoplankton, fish that feed on zooplankton)… No polar ice over there will be no vertical currents…could reduce the rise of nutrients to the surface and therefore PHYTOPLANKTON SHORTAGE MAY DECREASING ITS VITAL CONTRIBUTION OF OXYGEN TO THE ATMOSPHERE (90 %)…fish…the sea it could almost stratified into horizontal layers with little energetic movement of water masses in vertically which is what removes fertilizer nutrients from the bottom… Besides lowering salinity of the sea, for that great contribution of freshwater to melt the Poles, will increase evaporation (ebullioscopy: the less salt has, more evaporates) producing gigantic storm clouds as have never seen, that together with altering of the ocean currents, could cool areas of the Planet causing a new ice age… Warming…invasion of tropical diseases carried by their transfer agents, already without the “general winter” containig them would fall upon the World like a plague…and less oxygen in the Atmosphere… Is not known to be worse… Go choosing.

  16. tonyon says:

    …the beginning of the End of the World (no polar ice: the countdown has already begun)… the World is silenced by politicians and their armies and their control of the media by the religious. They are leading the Planet to catastrophe worrying only of the economy, “their” economy. Politicians do not want to know anything about climate change, even bothers to talk topic, do not care about anything other than “utilize” their way through the power to… ((Scientists say: “…Examining 20,000 data points, the researchers showed that the Southern Ocean surface has freshened during the last 60 years. They also found that vertical gradients of salinity and density have increased in the Southern Ocean, suggesting that mixing has been reduced. Seven of the models suggest that increased freshwater in the Southern Ocean could stop the convection from occurring altogether by 2030, and most models show strong decreases in convection during the 21st century, reducing the Antarctic Bottom Water´s formation. The absence of polynyas in recent decades colud mean that heat is getting trapped in the deeper ocean, possibly contributing to the recent “hiatus” in global atmospheric warming and the increase in Antarctic sea ice extent that have been observed in recent years.””))… Scientists checking that there can be NO and CONVECTION in 2030 in the stratified ocean with almost freshwater surface…the beginning of the End of the World…and the experts interested in Laws POLITICIANS not even know what it is and looking elsewhere unsigned serious international protocols that IMMEDIATELY STOP AROUND THE PLANET POURING OF CONTAMINATION. It´s the economy…

Leave a Reply