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Climate is the average of a series of weather events. Therefore as climate changes in New England, from both natural and human-induced causes, the number of particular weather events (such as noreasters, ice storms, and tornadoes) may also increase or decrease. Similarly, the magnitude of these individual events may lessen, or more alarmingly, increase with these changes. As a result, the greatest impact of future climatic change on New England may come in the form of changes in the number and intensity of extreme events and not necessarily average climatic changes that occur over decades or longer time periods. The importance to society of these distinct climatic events is that they can alter lives forever and potentially very quickly (i.e., within minutes, hours or just a few days). On the other hand, a very cold summer that results in poor agricultural yields, or a poor tourist season, can also be considered an extreme climatic event. Of course, what we all want to know is:
How will extreme events impact New England in the future?
The most reliable way to characterize the nature of extreme events and what
may happen in the future is to look at the characteristics of these events in
the past. By examining such events, we hope to learn how they may have varied
in the past, and how they affected the various distinct regions within New England.
We also need to examine past magnitudes of these events, their frequencies,
and whether trends over time exist for particular types of events, for example,
whether the number of exceptionally strong noreasters increased over the
past few centuries. A knowledge of such events may allow us to answer the following
general questions:
Did particular types of events occur more frequently in the past then they have in the last few years or even in the 1990s as a whole?
What type of trends do we see in the past that may have a bearing on what will happen in the future?
To begin to answer these questions, we have started to examine various sources
of data. One is existing instrumental records from meteorological stations across
the region. Most of these records span the last century, although a few may
cover the last 200 years. To extend our record beyond the last one to two centuries,
we are compiling and evaluating daily weather accounts recorded in personal
diaries, journals, and almanacs, as well as other types of historical data (e.g.,
dates of apple harvest and "ice-out" on area lakes) useful in evaluating changes
in seasonal conditions over time. These records provide detailed information
on not only how these events have varied in the past, but also how they influenced
earlier generations of New Englanders.
Following are a few examples of how extreme climatic events (blizzards, ice
storms, hurricanes, rainstorms, tornadoes) have varied over the recent past.
Several major snow storms have impacted New England in the 1990s, such as
the March 1993 "superstorm" and the large blizzard of 1996, leading to the question
of whether we are in a trend of increasing noreasters, either in number
or in magnitude or both. To answer this question as well as to evaluate the
record of the number of snow storms in general, the daily number of snowfalls
of 1-5 inches (Figure 3.1) and of > 5 inches (Figure
3.2) for Durham, NH (seacoast region) and Hanover, NH (inland site) are
plotted beginning with the winter of 1926-1927.
Several interesting results that warrant our continued investigation into
possible causes for these patterns can be seen in these records. Beginning with
the smaller snowfalls (Figure
3.1), the most obvious finding is the greater number of snow events that
occur in Hanover compared to Durham. The average number of 1-5 inch snows per
year in Hanover over the last 50+ years is almost 16 snows per year compared
to about 11 annually in Durham. Such a finding is not unexpected as there are
fewer storms that turn to rain or fall completely as rain in Hanover, whereas
the warming impact of the ocean changes much solid precipitation to liquid in
Durham. Of greater interest is the apparent decreasing trend in the number of
snowstorms per year at both sites over this 50+ year record. In general, there
were a greater number of years with an average or greater than average number
of 1-5 inch snowfalls in the late 1920s to early 1940s than in more recent times.
The lowest number of 1-5 inch snows occurs at both sites since about 1980, although
there seems to be an increase in the number of storms toward the long-term average
in the later part of the 1990s.
Continuing investigation into these records including the use of records from
other stations around New Hampshire and New England will lead to a more thorough
answer to questions such as:
What is the significance of this general trend to decreasing small snow events in recent years?
Is it a function of climate warming that has resulted in a greater number of rain events in the
winter over the past two decades compared to the 1920s and 1930s or something else?
Is the frequency of these smaller snowstorms in a
declining trend or are the trends more variable and fluctuating?
The average number of daily accumulations 5
inches, and thus the greatest number of snowfalls that probably originate from noreasters,
is 3.5 snowfalls per year at both Durham and Hanover. In this case, the greater proximity of Durham
to the coast actually results in an equal number of larger snows in the seacoast region of
New Hampshire compared to further inland. This scenario reflects the tremendous importance of the
track of coastal storms on New Hampshire and New England snowfall totals. A greater number of storms
close to the coast will bring a higher number of 5 inch
snows to the Hanover area and less to Durham because snow
often will change to rain along the coast. If the main storm track is more frequently found farther
offshore, there will be a greater number of 5 inch
snowfalls in Durham and less in Hanover, since Hanover is farther from the center of such storms.
We discuss the long-term trend in these larger snowfalls below. As for the total number of snowfall
days, we conclude that there are a greater number of total snowfall events further inland in New
Hampshire, but there appears to be an equal number of large storms per year across the region.
Continued investigations may further support these initial findings or we may find that there are
different trends along the New England coast as a function of latitude.
The long-term trend in the number of larger storms appears to be more variable
than that of the general decline in 1-5 inch snowfalls over the 50+ years of
record. At both sites (Figure
3.2) the greatest number of larger accumulations consistently occurred
from roughly the mid-1950s to the late 1970s/early 1980s. The period with the
greatest number of large storms per year is the decade from the late 1960s to
the late 1970s. There are other years with an abundant number of moderate to
larger blizzards such as in the 1930s and 1940s and again in the early 1990s,
but they do not occur as frequently as they did in the mid-1950s to late 1970s.Given these initial findings, we ask:
Is there a discernible cyclicity in the number of larger snowfalls across New Hampshire and New England?
To answer this question more completely, it will be necessary to evaluate
other snowfall records from around the region, especially at coastal sites such
as Boston and Portland, for comparison with other inland sites. Information
gathered from as many sites as possible will help us generate and then answer
other questions such as:
How has the spatial variability in the number and magnitude of noreasters changed over time?
The January 1998 ice storm clearly was a major event in New England history
(Figure 3.3), but how does
it stand up to other ice storms of the past?
Compilations by Ludlum (1976) show that there have been several major ice
storms in various parts of New England over the past two centuries. Perhaps
the greatest of these was the 26-29 November 1921 storm. Seventy-five hours
of rain, freezing rain, sleet and snow fell over central and eastern Massachusetts
producing slightly over 4 inches of mixed precipitation in Worcester. Ice was
2 inches thick on many power lines and over 100,000 trees were damaged or destroyed.
More recently, a 36-hour period of mixed precipitation and freezing rain in
December of 1973 produced total precipitation amounts between 1 and 3 inches
in parts of Connecticut. Almost one third of the state was without power and
tree damage was estimated to be greater than the 1938 hurricane. Other storms
throughout New England in the early 1900s and late 1800s are known to have produced
large amounts of mixed precipitation, such as the 7 inches of sleet and ice
in northwest Connecticut in February 1898. Although past ice storms may have
produced local damage similar to the ice storm of 1998, they pale in comparison
to the spatial extent of the damage from the 1998 storm. In addition to the
extensive damage in New Hampshire shown in Figure
3.3 , severe damage also occurred in Maine, Vermont, upstate New York and
southern Quebec. Because the distribution of damage from past ice storms is
not easily compiled, identifying any trends in the number and severity of ice
storms over time warrants our continued investigation of this type of climatic
event. Surely New England will feel the effects of future storms as we become
more susceptible to their widespread impact with increasing population, and
modern reliance on electricity, automobile travel, and communication.
Hurricanes and tropical storms are often classified as the "greatest storms
on earth." Although wind speeds in the most powerful hurricanes are not as intense
as the most powerful tornadoes, hurricanes encompass a much larger area and
can produce damage not only from high winds, but also from storm
surge and heavy rainfall. Vast regions can feel the effects of these storms,
even locations at great distance from a storm center can be affected because
of the wave energy and rainfall that is generated.
Surprisingly, the year with the highest number of storms making landfall in
the region was 1888 with three (figure
3.4). No other year since has experienced this many tropical storms and
hurricanes. There is evidence of temporal clustering of events. For example,
during a five-year period from 1896 through 1900, each year experienced one
storm event; for the following 11 straight years, 1905-1915, New England had
no landfalling storms. The three-year period 1959-1961 had five events, as did
1971-1973.
New England hurricanes generally originate near the Cape Verde Islands or
near Bermuda. Their paths exhibit very little curvature while taking a northerly
path towards the New England coast (Vega and Binkley, 1994). New England-bound
tropical storm systems can maintain much of their intensity as a result of their
trajectory over the warm Gulf Stream current, which produces warm sea surface
temperatures along the East Coast all the way to the shores of Long Island,
Rhode Island, and the south shore of Cape Cod. As a result, southern New England
is most vulnerable to hurricane landfall, with Cape Cod having the highest average
frequency of hurricane force winds, averaging one occurrence every 14 years.
Most of Rhode Island and Connecticut average one occurrence every 17 years,
and Maine experiences winds of hurricane strength about once every 20 to 25
years (Simpson and Riehl, 1981). Direct landfall of hurricanes has extremely
low probabilities along the eastern Massachusetts and New Hampshire coastline,
although these areas are affected by hurricanes making landfall elsewhere in
the region.
There are many years on record with no landfalling hurricanes, but near misses
are prevalent; (e.g., 1937 had five storms pass near New England) with eventual
landfall in the Maritimes of Canada. More recently, in 1996, Hurricanes Edouard
and Hortense gave New Englanders a scare as they churned up the East Coast,
before veering away from the area. In such instances, the storms can generate
enough wave energy, and sometimes storm surge, that coastal erosion and flooding
can cause serious damage. High winds can also be generated in the coastal zone
in these cases. Also, a number of storms have made landfall much farther south,
e.g., along the Gulf of Mexico coast or along the east coast in the southern
United States, but are steered to New England over land. For example in 1979,
Hurricane David made landfall in South Carolina, then passed through the mid-Atlantic
states to New York and finally passed through Vermont, New Hampshire, and Maine.
That same year, Hurricane Frederick made landfall near Mobile, Alabama, and
over land made it to northern Vermont and Maine. Such storms arrive here in
a weakened condition or as storm remnants, but their impacts can be significant.
For example, Hurricane Bertha in 1996 made landfall in North Carolina and traveled
inland to New England where it still was able to produce very heavy rainfall
region wide.
Despite their rare appearances, tropical storms and hurricanes tend to have a large impact in the region because of the high population density found in the New England coastal zone. Perhaps the most notorious New England hurricane was the Hurricane of 1938, which was a Category 3 hurricane, with winds speeds between 111 and 130 mph. This storm made landfall over Long Island, New York, and western Connecticut, and then took a northerly path through western Massachusetts and western Vermont, with a forward velocity of over 60 mph (Ludlum, 1976). It was the 21st most powerful storm to strike the United States in the 20th century, yet was the fourth deadliest in the United States, with 600 deaths attributed directly to it and its aftermath. Part of the explanation for the high death toll stems from the high population base that was affected; in addition, there was little notice that the storm was even coming. Storm surge was up to seventeen feet in some locations in Rhode Island and Massachusetts, with reports of waves between 30 and 40 feet high (Ludlum, 1976). Over $4 billion (adjusted for inflation) in damages were incurred, which ranks as the eighth most costly storm in United States history.
Surprisingly, the Hurricane of 1938 was only the second most powerful to make
landfall in New England (Table 1). Hurricane Gloria in 1985 was the most powerful
to make landfall here, packing winds over 140 mph. In contrast to 1938, however,
emergency preparedness was much improved, and Hurricane Gloria did not take
the same toll in human lives, nor in property damage. Interestingly, the fourth
and fifth most powerful storms to strike New England occurred just 11 days apart
in 1954.
Could it be possible that tropical storms and hurricanes are becoming less intense and less frequent in New England?
Given the dates presented in Table 1 (in addition to the time series in Figure
3.4), there is no suggestion that New England hurricanes and tropical storms
are now getting more intense or frequent, which is in general agreement with
the results of Henderson-Sellers et al. (1998) for the North Atlantic and North
Pacific basins. In fact, four of the top five events this century occurred prior
to 1955.
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Five most Intense New England Hurricanes, 1900-97.
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|
Hurricane
|
Date |
Pressure
in Millibars
|
|
Gloria
|
27
September 1985
|
942 |
|
Number 4-1938 |
21
September 1938
|
946 |
|
Number 7-1944
|
15
September 1944
|
947 |
|
Edna |
11
September 1954
|
954 |
|
Carol |
31
August 1954
|
960 |
|
Source is the National Hurricane Center. Since accurate wind speed data are lacking for many hurricanes in the earlier decades examined, the central barometric pressure
of the hurricanes are posted as an index for storm strength, with lower pressure relating to a stronger storm.
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New England can experience heavy rainfall from three sources:
- hurricanes/tropical
- storms and their remnants, noreasters or other synoptic-scale mid-latitude
cyclones
- localized storms that are generated by free-convection, particularly in summer.
Summertime free-convection can produce very extreme
rainfall, but is typically limited in area and generally of lesser magnitude
than those rainstorms produced by larger-scale features. Therefore, this discussion
focuses on the more regional heavy rains produced by the two former mechanisms.
Table 2 displays the largest precipitation events recorded in New England
over the past 50 years. The largest single-day precipitation event recorded
in New England was 18.15 inches at Westfield, Massachusetts, produced by Hurricane
Diane in late August 1955. In all, this single event produced 19.75 inches of
rainfall at Westfield over three days (18-20 August 1955), which is the single
largest rainfall event in New England (Keim, 1998). One-day rainfall totals
from this event were in excess of 10 inches at numerous sites in Massachusetts
and Connecticut. It was particularly damaging because the storm followed the
heavy rains produced by Hurricane Connie in southern New England on 12-13 August.
As a result of these two storms, the month of August 1955 went into the record
books as one of the all-time record months for total precipitation, with values
reaching over 25 inches for parts of Massachusetts and Connecticut (Figure
3.5).
The second greatest singe-day rainfall event occurred in late October of 1996
and is detailed by Keim (1998). This event, produced by a "continental noreaster,"
generated the heaviest rainfall values along the east coast of New England from
Boston, Massachusetts, to Portland, Maine (Figure
3.6). From this event, Camp Ellis and Gorham, Maine, recorded storm rainfall
totals over three days of 19.2 and 19.0 inches, respectively. Also, Maine and
New Hampshire set all-time records for one-day rainfall events during this storm.
Analysis of rainfall extremes in the region revealed that the event was in gross
excess of a 100-year storm event between Boston and Portland, and at some locations
in Maine, it was close to a 500-year storm event. In other words, a storm of
this magnitude or greater could be expected to occur only once every 500 years,
on the average, or that any single year has a 1/5th of 1 percent chance of experiencing
a storm like this. Impacts included river-basin flooding, loss of potable water
supplies, and road and bridge damage.
Five of the eight storms listed in Table 2 occurred in the months from
August to October, suggesting that these events are usually tropical, in the
form of a hurricane or tropical storm. However, some of the most powerful noreasters
can also occur in October (Dolan and Davis, 1992), and these weather systems
are generators of heavy rainfall. Of these eight events, all but the storms
on 6 June 1982, 31 December 1948, and 16 October 1955 had some tropical component.
Even the continental noreaster on 21 October 1996 had some of its moisture
contributed by Hurricane Lili, located in the Atlantic at the time. Interaction
between tropical storms/hurricanes and mid-latitude storm systems is not unprecedented
in New England; e.g., the Vermont flood of 1927 was produced under similar circumstances.
Though not included in Table 2, this event produced 9.65 inches of rain at Somerset,
Vermont, with estimates of 15 inches at higher elevations nearby (Ludlum, 1976).
Based on Table 2, there is no suggestion that the heaviest of rainfall events
are increasing as a result of global warming, since half of these events occurred
in the first 8 years (1948-1955) under examination. However, the 1990s have
experienced some unusual rain and flood events; e.g., Portsmouth, New Hampshire
had two events in the past three years, one of which exceeded a 100-year event
(October 1996) and the other exceeded a 50-year event (June 1998). These results
illustrate the difficulty in trying to understand what is happening based on
a fifty-year record, and the urgency of creating a much longer one.
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Largest 1-day Precipitation Events Recorded in New England, 1948-97.
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|
Location
|
Date
|
Rainfall (in.)
|
|
Westfield, MA
|
19 August 1955
|
18.15 |
|
Portland, ME
|
21 October 1996
|
11.71 |
|
Cockaponset,
RI
|
6 June 1982
|
10.47 |
|
Torrington, CT |
31 December 1948
|
8.91 |
|
Middleton, MA |
6 October
1962
|
8.64 |
|
Woods Hole, MA |
3 September
1972
|
8.55 |
|
Norfolk, CT |
16 October
1955
|
8.20 |
|
Brunswick, ME |
11 September
1954
|
8.05 |
|
Source is the New Hampshire State Climate Office, University of New Hampshire.
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Tornadoes are arguably the most violent storms on earth. They can have wind
speeds well over 250 mph, with documented examples of trucks and railroad coaches
being lifted off of the ground and dropped hundreds of feet away (Lutgens and
Tarbuck, 1998). Similarly, large trees are easily uprooted, and houses present
little resistance to the most powerful tornadoes. Fortunately, tornado outbreaks
are relatively rare in New England when compared to frequencies on the Great
Plains of the United States, e.g., Texas, Oklahoma, Kansas, and Nebraska. In
fact, New England gets the fewest tornadoes of any region east of the Rocky
Mountains. However, despite the low occurrence rate of these violent storms,
there are documented cases in all corners of New England ranging from the Allagash
Valley, Maine, in the northeast, to Nantucket Island in the southeast, Greenwich,
Connecticut, in the southwest, and St. Albans, Vermont, in the northwest (Ludlum,
1976). The average New England tornado occurs in summer, in the late afternoon,
and travels from southwest to northeast at a speed between 25 and 40 mph.
In New England, Massachusetts has the highest number of documented tornadoes
(and obviously the highest annual average) and Rhode Island has the smallest
number of documented events (Table 3). The area most affected by tornadoes lies
just to the east of the Berkshires in north-central Massachusetts (Leathers,
1994). Maine, New Hampshire and Connecticut are close in number in their statewide
tornado occurrence rates, averaging between 1.4 and 1.8 per year. However, tornado
frequencies in New England pale in comparison to the Great Plains, which receive
approximately ten times as many tornadoes as New England. For example, compare
these averages to states like Texas and Oklahoma which reported 5860 (125 per
year) and 2420 (51 per year) tornadoes, respectively, over this same time period.
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Number of Documented Tornadoes for each N.E. State, 1950-96.
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|
State
|
Tornado Reports
|
Average Per
Year
|
|
Massachusetts
|
134 |
2.9 |
|
Maine
|
83 |
1.8 |
|
New Hampshire |
73 |
1.6 |
|
Connecticut
|
65 |
1.4 |
|
Vermont
|
32 |
0.7 |
|
Rhode Island |
8
|
0.2 |
|
Source is the National
Severe Storms Laboratory.
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New England gets far fewer tornadoes than most other states because of its
location. It is situated far enough north that the jet stream orientation for
much of the year is located south of New England and relatively cool temperatures
prevail in the region. The cooler temperatures serve to stabilize the atmosphere,
which suppresses opportunities for the development of tornadoes. In summer (July
and August, in particular), the jet stream moves farther north, bringing warmer
conditions and greater instability to New England. This instability results
in greater thunderstorm activity and the potential for tornado development.
However, the cold water off the east coast of New England in summer lessens
the intensity of thunderstorms, which are the purveyors of tornado outbreaks.
As a result, tornadoes are rare within about 15 miles of the coast. Although
the values in Table 3 are not adjusted for area, the relatively small number
of events in Rhode Island is partly driven by its coastal location, even though
the water temperatures are warmer in this region than along the eastern coastal
zone of New England.
By far, the worst to strike in New England was the Worcester tornado of 9 June 1953 (Table 4). The Worcester tornado touched down at Petersham, Massachusetts, and took a path east-southeastward to Southboro, Massachusetts, covering 46 miles and lasting an hour and twenty minutes. Nested within the same storm system, two other tornadoes were spawned that day in Exeter, New Hampshire, and Sutton, Massachusetts. Clearly this was one of the worst tornado days in New England history, with 90 deaths from the one tornado alone (mostly in Worcester) and 94 from the three tornadoes combined (Ludlum, 1976). The second worst tornado (in New York and Massachusetts) led to 8 deaths. There have only been 17 tornadoes between 1880 and 1995 that are known to have taken lives in New England. Even weaker tornadoes can take lives as was the case on July 4, 1898, in Hampton, New Hampshire.
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Most Deadly New England Tornadoes, 1880-95.
|
|
County, State |
Date |
Strength |
Est. Wind speed (mph)
|
Injured |
Killed |
|
Worcester, MA |
9 June 1953
|
F4
|
207-260 |
1288 |
90 |
|
Essex, MA
|
26 July 1890
|
F3
|
158-206 |
63
|
8
|
Columbia, NY-
Berkshire, MA
|
28 August
1973
|
F4
|
207-260 |
31
|
4
|
|
Hampton, NH
|
4 July 1898
|
F1
|
73-112 |
120
|
3
|
Hartford, CT-
Hampden, MA
|
3 October 1979
|
F4
|
207-260 |
500
|
3
|
|
Berkshire, MA
|
29 May 1995
|
F3 |
158-206 |
24 |
3 |
|
Sources are Grazulius (1991) and The Tornado Project, St Johnsbury, Vermont found
on the world wide web at http://www.tornadoproject.com/.
|
Figure 3.7 displays an annual
time series of tornado frequencies in New England. This series includes all
tornadoes of F1 strength (on the Fujita
scale) or greater, which corresponds to wind speeds of 73 mph or more,
but does not include F0 tornadoes. As shown, there were few powerful tornadoes
near the turn of the 20th century, with some clustering of events beginning
near 1950 and continuing into the early 1970s. The lower frequency in the early
portion of the time series could simply be the result of lower population densities,
lower reporting rates, and poor communication. The biggest year on record was
1972, which included a total of four events. Frequencies appear to have declined
in the 1980s and 1990s, which is a time when global temperatures were largely
above normal. It is probable that the recent decline is weather-related and
not a societal artifact, as is likely in the earlier portion of the time series.
This decline over the past two decades, however, is in contrast to the rest
of the United States, where the 1990s have seen unprecedented numbers of reported
tornadoes.
One of the most famous single events to influence New England climate, and
an event that has been well documented in the annals of New England climate,
was the 1815 volcanic eruption of Tambora, Indonesia, the largest known historical
eruption in the world. Although situated almost directly on the equator and
on the other side of the world, this extremely large eruption influenced global
climate, with an especially severe impact on New England. The large amount of
sulfuric acid eventually produced in the stratosphere
by sulfur-rich gases released during the eruption blocked out solar radiation,
resulting in a cooling of Earths surface for several years after the eruption.
This process led to the famous "Year Without a Summer" of 1816. Many diaries
and newspaper accounts from around New England make particular note of that
cold summer including accumulating snow in early June in northern New England
with flurries as far south as Massachusetts and Connecticut and exceptionally
cold nights in July and early August that resulted in isolated pockets of frost
(Ludlum, 1976). These highly unusual summer phenomena led to great crop losses
(Stommel and Stommel, 1983).
Certainly the impact of the Tambora eruption was phenomenal in the annals of New England climate, but this is not to say that only an eruption of that size can have an impact on climate in this area. An evaluation of annual temperature and especially summer temperatures (June, July, August) in Durham, NH, over almost the last 100 years shows that some of the coolest summers
follow major volcanic eruptions (Figure 3.8). Individuals whose livelihood is
dependent on summer climatic conditions should be well aware of the potential for a very cool summer following the next major volcanic eruption.
However, it is also important to realize that volcanic eruptions are just one of the many factors that force and control New Englands climate. In the record of Durham
annual and summer temperatures (Figure 3.8), there are other summers that are
below the long-term trends. Moreover, it is clear that there is a periodicity in temperature trends in Durham such as the overall warmer conditions of the 1950s followed by the cooler 1960s. Our investigations are focusing on defining any long-term trends and the periodicity of these shorter-term fluctuations in temperature, both of which may be related to other climate-forcing factors such as variability in Earths orbital cycles, solar radiation, El Niño events, and greenhouse gases. Considering the tremendous impact and public awareness of the 1997-1998 El Niño event, we are evaluating the impact of other El Niño events (of varying intensity) during this past century to quantify the range of climatic impact from El Niño in New England. We need to "single-out" the impact of each of these forcing factors, including the volcanic forcing component, on New Englands climate to better inform the general public on what may be expected in the future.
In contrast to the frequently referenced cold summer of 1816 throughout New
England, a series of snow storms between 17 and 24 February 1893 has not been
given the recognition it may deserve as one of New England's greatest snow events.
Most compilations of blizzards, and thus nor'easters
, in New England, highlight the storms of 1717 and 1888 as among the greatest
in historical time (e.g., Ludlum, 1976; Kocin and Uccellini, 1990). For instance,
a series of four storms between 27 February and 7 March 1717 dumped upwards
of 35-45 inches across southern New England, while the 11-14 March 1888 blizzard
dumped up to 50 inches of snow in some parts of central Connecticut and 30-36
inches in southern New Hampshire (Ludlum, 1976). The large amount of snow from
the 1888 blizzard resulted from a "stalled" low
pressure system off of Block Island, Rhode Island, and thus from a single
storm.
However, the diary of George H. Lang of Rye,
NH, (diary dates 1871-1901) makes particular note of the series of snow storms between 17 and 24 February 1893. Five separate storms in quick succession resulted in the greatest snowfall accumulation that he had ever seen as he "shoveled out whole length of the district." He was 65 at the time of these storms. Lang notes that "a rough and tough old East snow storm set in" on 12 March 1888, and that it was "one of the rough ones for years, " but Lang makes no note of tremendous snowfalls in Rye like he did for the 1893 storms. Similarly, the diary of Seth Dame, Nottingham, NH, makes note of a blizzard on 20 February 1893 and a second blizzard on 22 February 1893. Both of these storms dropped about a foot of snow, and together with two 3+ inch accumulations on the days before and after these blizzards, a total of over 30 inches fell between 17 and 24 February 1893 in Nottingham. Dame also noted that a "severe snowstorm"
occurred on 12 March 1888, but he makes no additional comments which would indicate that it was comparable to the 1893 snows.
Surprisingly, the only note in the compilation of extreme weather events by Ludlum (1976) that references an exceptionally large snowfall in late February of 1893 is that for Monroe in the Berkshires of western Massachusetts. That town recorded 53 inches over a six day period ending on 25 February which contributed to the snowiest February as well as the snowiest winter (1892-1893) on record in Monroe, at least prior to Ludlums compilation in 1976. Thus, the amount of snowfall in western Massachusetts to eastern New Hampshire between 19 and 25 February 1893 may have been equivalent to, if not more than, that of the great blizzard of 1888. In addition, both the Lang and Dame diaries note a severe storm on 13 February 1893 that produced a foot of snow in Nottingham. Southeastern New Hampshire was covered by over 40 inches of snow between 13 and 24 February 1893, amounts similar to that for the 1717 great snow.
The diaries of George H. Lang and Seth Dame and their accounts of the tremendous
snows of February 1893 in the seacoast of New Hampshire as compared to those
for the "Blizzard of 88" highlight the great potential for extreme events
in New England climate. Our initial investigations into the wealth of information
available in written records, such as the accounts of the tremendous snows of
February 1893, also show the limited number of compilations of past climatic
events now in existence. A thorough understanding of variability in the system
requires the compilation of climatic records from across the area. No single
record will provide the details needed to reconstruct what happened in the past
and ultimately postulate what may happen in the future. This is particularly
true for the extreme events discussed as well as other types of extreme events
like hot spells, cold waves, floods and droughts. Everybody is well aware of
the problems of predicting snowfall totals across New England with the approach
of a coastal storm. Conditions can vary from no precipitation to rain to mixed
precipitation to almost two feet of snow over a zone of less than 50-60 miles.
It is important to use all available information to isolate trends in these
extreme events and to understand the potential impact they had and could have
on New England society both as a whole and within the various parts of the region.
References
Dolan, R., and Davis, R.E. 1992. Rating Northeasters. Mariners Weather Log, Winter 1992:4-11.
Henderson-Sellers, A., Zhang, H., Berz, G., Emanual, K., Gray, W., Landsea, C., Holland, G., Lighthill, J., Shieh, S-L., Webster, P., and McGuffle, K. 1998. Tropical Cyclones and Global Climate Change: A Post-IPCC Assessment. Bulletin of the American Meteorological Society 79:19-38.
Keim, B.D. 1998. Record Precipitation Totals from the Coastal New England Rainstorm of 20-21 October 1996. Bulletin of the American Meteorological Society 79: 1061-1067.
Kocin, P.J., and Uccellini, L.W. 1990. Snowstorms along the Northeastern Coast of the United States: 1955 to 1985. American Meteorological Society: Boston.
Leathers, D.J. 1994. A Tornado Climatology for the Northeastern United States. Publication No. RR 94-2, Northeast Regional Climate Center: Ithaca, New York.
Ludlum, D. 1976. The Country Journal: New England Weather Book. Houghton Mifflin: Boston.
Simpson, R.H., and Riehl, H. 1981. The Hurricane and Its Impact. Louisiana State University Press: Baton Rouge, Louisiana.
Stommel, H., and Stommel, E. 1983. Volcano Weather. Seven Seas Press: Newport, Rhode Island.
Report by:
Dr. Gregory A. Zielinski, Research Associate Professor in the Climate Change Research Center in the Institute for the Study of Earth, Oceans and Space and the Department of Earth Sciences.
Dr. Barry Keim, New Hampshire State Climatologist and Assistant Professor in the Department of Geography and the Climate Change Research Center in the Institute for the Study of Earth, Oceans and Space.
Mr. Justin Cox, Iola Hubbard Climate Change Endowment Undergraduate Summer Fellow.
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