Guest post by Richard Keen, PhD
I’m sure by now every snow freak in the Northeast U.S. has pored over the “Billboard Top 40” (actually, 41) list of major snow storms since 1955. If you haven’t, go to “The Northeast Snowfall Impact Scale (NESIS)”, posted at http://www.ncdc.noaa.gov/snow-and-ice/nesis.php
I’d like to thank our friends at the NWS and NCDC, Paul Kocin, Louis Uccellini, Jay Lawrimore, and Michael Squires, for their work at putting this together. For me it brings back the memories of the great school-closing dumps of my early days in Philadelphia. I “survived” numbers 3, 5, and 6 on the list, and made enough money shoveling neighbors out of numbers 5, 21, and 26 to buy my second telescope. Number 30 left our house without power for five days, during which we ate hot dogs cooked in the fireplace. But enough of the memories. How are today’s kids in the Northeast faring in their quest to earn enough money digging snow to buy themselves telescopes?
To put the storms in a timewise perspective, here’s a chart of each event, plotted by date and NESIS magnitude.
Kocin et al. have simplified the storm magnitudes into categories (1 to 5, with “major” being 3 and above). Anecdotally, only two winters have had three “major” storms, 1960-61 (when I earned my telescope) and 2009-10.
Apparently today’s kids are no better or worse off. There’s 55 seasons (54 full winters and two half winters) of storms represented in the Kocin et al. catalog, so I’ve split the record into two halves to see if recent years have had more or fewer of these great snow storms. Results are summarized in the table.
The split couldn’t be more even, with 20 storms in the first 27.5 seasons and 21 in the second 27.5 winters. The accumulated NESIS index (sum of the NESIS for the 20 or 21 storms) is almost as evenly split. The implications for climate change are that as far as Northeast snow storms are concerned, there is no change.
I now live in Colorado, where I am the co-op observer for Coal Creek Canyon, 8950 feet up in the foothills west of Denver. An endearing feature of the local climate is the frequent occurrence of 40-inch-plus snow storms. I now have 32 years of snow storm records, and as with the Northeast snow storms, the 40-inch events are evenly split (7 and 7) between the first and last halves of the record.
You may read more about the Colorado storms in “Thirty years in the Bull’s-eye: a climatology of meter-class snow storms in the Front Range foothills”, by Richard Keen,
5th annual Hydrologic Sciences Student Research Symposium, University of Colorado, Boulder, April 1-2, 2010, posted at
http://hydrosciences.colorado.edu/symposium/abstract_details.php?abstract_id=26
Conclusion: there appears to be little or no change in the frequency of major snow storms over the past 30 to 55 years, at least in the Northeast U.S. and in the Front Range foothills of Colorado.
I’m just happy that up here in BC we only caught the edge of that system.
Seems though the tree- hugger s have STFU, power outage has a way of convincing
“those types” that loggers clearing cutlines is not a bad thing.
d
HenryP says:
January 29, 2011 at 10:45 am
BTW
where is Canmore?
It’s in the mountains west of Calgary and east of Banff.
http://www.canmorealberta.com/maps/alberta
Looking at the chart of NE snowstorms in the chart above, it seems to me that the major snowstorms are concentrated in the first and last years of the record. A plot of the moving 5 year average would show this more clearly.
So what we see is a U shaped graph which may have different mechanisms associated with each leg of the U. The fact that there are equal numbers of storms in the the first and second halves of a 55year record doesn’t really disprove that Global Warming is responsible for the recent upturn.
With all respect, Sir, I disagree.
They will not stop.
For the CACC taliban, real scientific data means nothing and exists only to be manipulated.
Regards,
Ming
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The whole point is that they don’t have a choice in the matter. We only have to convince the House Republicans, and by my way of thinking this is very persuasive argument.
Here in California we passed Prop 26, which means that voters have to approve any carbon taxes, fees, or fines.
Think of this as the memo that puts Arnold into retirement. No Climate Czar post. He’ll bow out quietly.
I like evidence. This is good.
The two whoopers around 95 are of some interest, but there is not enough data points to go beyond “random event”.
I spent most of my life in the Midwest and recall plenty of snowstorms. But living in a lake-effect snow belt is an entirely different experience. The snow belts are very localized, so a small population is adversely affected by it. The West Michigan snowbelt I lived in for 16 years averaged 100 inches of snow/year. The number of actual snowstorms were not great, but a steady wind over Lake Michigan could deposit 3-6 inches of snow in a few hours. I recall one December where it snowed at least 3 inches a day every day–the entire month! Needless to say, we had ice dams on our roof, etc.
Now I live in the Front Range of the Rockies, and I LOVE the 300 days/year of sunshine and the quickly-melting snow. I’m grateful when the mountains get lots of snow but equally grateful that the snow stays there.
North winds blow across the widest stretch of open water of Lake Superior , that’s what I always thought caused the higher snowfall totals around Marquette. I don’t think it’s really Marquette on the lake with the greatest snowfall, I believe its actually measured at the TV6 grounds 5 miles from the lake in the higher elevations closer to Negaunee.
Congratulations on the Pinewood Derby. Time well spent.
I am wondering if the NESIS scale would be a better representation of the effects of large snowfalls if the duration of the snow on the ground could be considered. When a second or third snowfall comes before any substntial melting and the snow pack gets deeper, this affects the perceptioin of snow severity, and may also substantially affect people’s lives.
Very interesting post Richard.
A few notes: The general correlation of frequency of larger storms during El Nino years and the snowiest months of the year for Colorado are related to the larger physical fact that warmer air can carry more moisture and during El Nino years there tends to be more warmth and moisture available. This is also indicated in the longer term glacial records from Greenland ice cores, where the warmer years (relatively) saw a greater rate of accumulation of snowfall. See: http://www.ncdc.noaa.gov/paleo/pubs/alley2000/alley2000.gif
As the above graph clear shows, warmer means greater snowfall rates as more moisture is avaiable. Of particular note in the graph above is the Younger Dryas period, the cooler period when the glaciers advanced EVEN THOUGH SNOWFALL RATES WERE LOWER. The reason is of course that glaciers advance more because of cooler summers when all the snow doesn’t melt, not because of larger rates of accumulation. Glacial periods are marked by lower temps and lower rates of accumulation, even though the glaciers advance. This basic physica fact is seen in ice cores from all over the world, but seems to be lost on some AGW skeptics, and I sort of half to laugh when AGW skeptics speak about large snowfalls as evidence AGAINST global warming when hundreds of thousands of years of ice core data tell us the exact opposite.
2010 was the wettest year on record on a global basis, but the presence of large snowfalls and rainfalls in any particular region of the planet are neither evidence for nor against the presence of anthropogenic factors in this warming.
Finally, I guess we need to get ready for cold here in Colorado early this week, though not much snow, as it will be too cold and the energy from the storm coming from the wrong (i.e. not the pacific) direction.
Dr. Keen neglected to mention that the NESIS scale includes a population component. That inevitably weights recent Northeastern storms more heavily than past Northeastern storms. That is like saying hurricanes are more destructive today than 50 years ago. Of course! More people are in the way. So how bad are the storms in absolute terms?
R. Gates says:
January 30, 2011 at 10:07 am
2010 was the wettest year on record on a global basis,
I wonder how R. Gates came to this conclusion when NASA’s dataset only includes 14 years (1988-2001)?
http://nvap.stcnet.com/
Perhaps Gates is a God with unlimited knowledge that he can see results that are hidden from every other person on the planet.
Regardless of his fantastic reading of ice core predictive capabilities, the NVAP data say that there is no trend in total precipitable water (TPW) or layered water vapor on decadal scales.
“By examining the 12 year record [1988-1999], a decrease of TPW at a rate of -0.29 mm / decade is observed. This relationship is significant at the 95 % but not at the 99 % level. A downward trend would be intriguing since there should be a positive slope if a global warming signal was present. However, by subdividing the data into two halves (1988-1993) and 1994-1999, trends with opposite signs are detected. Since the trend is not robust by subdividing the data, we conclude the global TPW has no significant trend from the NVAP dataset studied here.”
Statement on using existing nasa water vapor nvap dataset 1988-2001 for trends
That’s the reason why you don’t see splashy trend charts of atmospheric water vapor anomalies next to GISS’ splashy trend charts of temperature.
Because if they told the truth, the whole truth, and nothing but the truth, even Ed Begley would be a pitchfork toting skeptic.
What is the unit of measurement on the y-axis in this graph? My recollection is that NESIS counted population affected, amongst other factors, and not simply snow volume (as it should). That would confound any interpretation of trends. Do the authors have any data on total snow volumes of these storms?
What I am curious to know is why so many people from Colorado are so active in the great AGW debate? As a percentage of the global population, I sense that Colorado, USA is highly over represented.
Kan says:
January 31, 2011 at 1:53 pm
UCAR.
Mark
R. Gates says:
January 30, 2011 at 10:07 am
“The general correlation of frequency of larger storms during El Nino years and the snowiest months of the year for Colorado are related to the larger physical fact that warmer air can carry more moisture and during El Nino years there tends to be more warmth and moisture available. This is also indicated in the longer term glacial records from Greenland ice cores, where the warmer years (relatively) saw a greater rate of accumulation of snowfall.”
Incorrect. El Nino amplifies the low-latitude jet and causes more lows to track across the southern US, where they can create upslope flow along the east side of the Rockies. In general, the southern US from California to Florida is COOLER and wetter during el Nino. Meanwhile, the Cascades and northern Plains get warmer winters with LESS snow. So where’s all that warmth related moisture? Your simple hypothesis that warmer = wetter does not work. Meanwhile, La Nina bring more snow to the West slope of Colorado, the Cascades, and the northern plains – but isn’t it supposed to be cooler and drier? Again, warmer = wetter NOT! It’s the storm tracks, as I’ve mentioned in earlier posts.
“Glacial periods are marked by lower temps and lower rates of accumulation, even though the glaciers advance. This basic physica fact is seen in ice cores from all over the world, but seems to be lost on some AGW skeptics”
Show me ice core results from Philadelphia that make your point! Greenland is a fair ways from Philly and Colorado, and the climate is rather different. A physical fact that you seem to miss is that the ice ages begin and grow when summers are cooler (as you note) but winters are warmer (with more moisture content and MORE snow), all due to orbital tilts and such (not greenhouse gases). Then the climate cools as the glaciers grow. In Glaciology this is called “Mass Balance”, a balance between accumulation and ablation. So both are equally relevant. But again, all this has nothing to do with Philly and Colorado.
“I sort of half to laugh when AGW skeptics speak about large snowfalls as evidence AGAINST global warming when hundreds of thousands of years of ice core data tell us the exact opposite.”
Read the story again. The point is that in Colorado and the Northeast the snow storms are NOT changing in frequency either way, and therefore cannot be used as evidence that AGW is occurring. Unless, of course, one subscribes to the very robust AGW hypothesis in which an increase, decrease, or no change in any and all atmospheric parameters are proof of warming (or cooling?)
starzmom says:
January 30, 2011 at 6:42 pm
“Dr. Keen neglected to mention that the NESIS scale includes a population component. That inevitably weights recent Northeastern storms more heavily than past Northeastern storms. That is like saying hurricanes are more destructive today than 50 years ago. Of course! More people are in the way. So how bad are the storms in absolute terms?”
Admittedly this is a bit unclear in the NOAA article about the NESIS scale, but my reading of it is that they weight the spot snowfalls by the population distribution in the 2000 census for all storms, and divide by the total population of the region in 2000. So population growth does not skew the NESIS index, but a 10 inch snow in center city Philadelphia counts more than a 10-inch snow in the south Jersey pine barrens.
I like for my measures of storm severity to depend only on the storm characteristics (and not, e.g., on population). Could you imagine if we pulled the same tactic to measure hurricane strength? Bunk NESIS. Gimme snow volume.
Taxpayer says:
Now I live in the Front Range of the Rockies, and I LOVE the 300 days/year of sunshine and the quickly-melting snow. I’m grateful when the mountains get lots of snow but equally grateful that the snow stays there
So you have 300 days per annum clear blue skies and starry nights? Can this be true? Where exactly is this? and which months are the dry and which months are the wet months?
I am asking this for a reason. I am looking for dry places to do some research. I hope you have a weather station in the neighborhood?
http://www.letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
Mark T- it is more than just UCAR. There are lots of folks not related to UCAR, or CSU that are engaged.