Physical Geography
Roaring
Brook Falls near St. Huberts in
the Adirondacks.
To understand and
to appreciate the geography of New York State, you first must know
something about the physical landscape.
The location of our lakes, rivers, mountains, and coastal lowlands has
determined the pattern of settlement in the state, as well as history
and cultural development.
Most of New York State is underlaid by sedimentary
rocks: sandstone, shale, limestone, and conglomerate. This tells
us that much of geologic history, the state was under water, especially
during the Paleozoic Era between 500 to 300 million years ago. Very
thick deposits formed at the bottom of that ancient sea, and the resulting
rock layers are visible in many places - the Niagara Gorge, the
Genesee Valley, the Finger Lakes, and the Hudson Valley
- just to name a few locations.
There are several
places, however, that show a different geologic past. Most of
New York City and the Hudson Highlands,
for example, have exposures of igneous and metamorphic rocks. This
tells us that these parts of the state had a violent history of
volcanism and colliding tectonic plates. At one time there were mountains
thousands of feet high, but they have eroded down to their roots.
The skyscrapers of Manhattan are anchored in these ancient mountain
cores.
The most unique
area of the state in many ways is the Adirondack Region.
It contains some of the oldest rocks in the country, over one billion
years old. They, too, are the cores of ancient mountains. In fact,
the Adirondacks are part of the great Canadian Shield. The region,
however, has recently been uplifted in a huge dome that dominates
the northeastern part of the state. In fact, it is still rising, by a
few millimeters per year. (Occasionally, there are minor earthquakes
in the Adirondacks). So we have the strange situation of young mountains
made of very old metamorphic rock. As a result, the Adirondacks form a
remote region, one of the last parts of New York to be settled. Much of
it is still wilderness today, much to the delight of its many visitors.
An excellent color relief map of New York can be
found at the Color Landform Atlas.
The highlands stand out very clearly: the Adirondacks
(in Northeast New York), the Allegheny Plateau/ Catskills (along
the southern border with Pennsylvania), and the Taconic Mountains/
Hudson Highlands (along the border with New England). These form
natural barriers for transportation and settlement. However, these
barriers are breached by some very important lowlands, that form a
giant sideways “T”. This shows up clearly on the relief map in green.
Along the eastern border of the state are the Champlain
and Hudson Valleys. And stretching across the center of the
state is the Mohawk Valley and the Lake Ontario Lowlands.
Other relatively flat regions include the St. Lawrence Valley,
the Lake Erie Plain, the Susquehanna Valley,
and Long Island. Most of New Yorkers live
in these lowlands, which should not be very surprising. (This shows
up very clearly on a satellite image of the United States at night
from NASA: http://antwrp.gsfc.nasa.gov/apod/image/usanight_dmsp_big.gif
Glaciation in New York
State: New York has been through many periods of mountain
building and uplift, separated by millions of years of erosion. One
such period occurred in very recent geologic time, the Ice Age. In fact,
it ended in New York only about 8000 years ago. The glaciers were about
one to two miles thick, and they covered almost all of the state, except
for a small section in Southwest New York, known as the Salamanca Re-entrant.
The moving ice sheets scoured and rounded the Adirondack
Mountains, and they dug out many deep "U-shaped" valleys, especially
in the Finger Lakes Region. Glacial erosion is responsible
for the fjord of the Hudson River. (Tides on the Hudson reach Albany).
The huge ice sheets carved out the basins that became the Great
Lakes (and the hundreds of smaller lakes found all over New York).
When the glaciers finally receded, they left behind
deposits of rocks and dirt, filling many valleys with rich, fertile
soil. These deposits are also visible throughout the state as drumlins
(Central New York/Finger Lakes) and moraines (Long
Island, and the Southern Tier). Some of these moraines that diverted
the courses of rivers in New York, such as the Genesee and the Allegheny
Rivers.
Finally, the meltwaters of the receding glaciers
had a major influence on the topography of New York. One of the
escape routes went down the Mohawk Valley. It deepened the valley,
and at Little Falls, it actually breached a divide, leaving
behind a low-level route that would one day become the Erie Canal.
The landscape of New York is in many ways unique to the
North American continent. The modifications made by the Ice Age have
had a major impact on the human and economic geography of the state
as well.
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Glacial till on Long Island's north
coast.
The Berby Hollow near Bristol, NY. This is a good
example of a glacial trough.
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New York's Climate:
All of New York lies in the Earth's temperate zone, since
the state's latitude lies between 40° and 45°N. All regions
experience four distinct seasons. Winters can be cold and snowy, and
summers often are hot and steamy. The colors of autumn are spectacular,
especially in the Adirondacks, the Catskills, and the
Finger Lakes areas. Spring can be a very unpredictable season, with
warm breezes one day, and snowfall (or even an ice storm) the next. We
New Yorkers love to complain about our weather, and dream of escaping
to Cancun in February. However, on the plus side, extreme weather events,
such as tornadoes and hurricanes, are not common. More about the seasons
of New York below…
The south shore of Lake Ontario is one of New
York's infamous Snow Belts.
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WINTER:
A popular joke goes something like this: "There
are four seasons in New York - almost winter, winter, still winter,
and construction." This is an exaggeration, of course, but winter is
very long! In the Adirondacks snow can stay
on the ground from October to May. On Long Island and New York City, snowfall
is less frequent, but it happens. Temperatures range from below zero in
Northern New York to around freezing (32 °F) in the south. The Tug
Hill Plateau, north of Rome, is one of the snowiest places in the country,
with around 200 inches (or more) annually. So, if you like outdoor winter
sports, New York is the place to be.
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Long Island does not
receive much snowfall, compared to other parts of the state. Also, being
surrounded by the ocean helps to modify the temperatures, so winters
are not bitterly cold here.
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SPRING:
Although
the calendar says spring begins on March 20th, most parts of the state
do not see real signs of the final end to winter until April. The danger
of frost lingers until early May, except on Long Island and the micro-
climates of the Great Lakes. Gradually, color returns to the landscape.
celebrated by Tulip Festivals in Albany or Lilac Festivals in Rochester.
Spring is one of the best times to visit New York City. (Summer in the
big city can be brutally hot. )
The Adirondacks have a special (and unwelcome) spring season:
black flies. When they are swarming, you don't want to be outside!
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Forsythia blooms in late-April in front of Buttermilk
Falls, Ithaca, NY.
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Springtime brings back tourism
to New York, an economic necessity for most parts of the state. Popular
destinations, like Cave of the Winds at Niagara Falls reopen
for the season. New Yorkers appreciate the end of winter more than people
in the Sun Belt, since we suffer more!
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Visitors from other parts of
the country are often surprised by how green New York State is during
the summer months. It is a time for regrowth and renewal. The warm
temperatures of summer and the abundant rainfall make it possible for
agriculture to flourish across the state, as shown in this dairy farm in
Farmington, near the Finger Lakes.
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Summer is long enough
in New York for the growth of Eastern Hardwood Forests. One exception is
the higher elevations and bogs of the Adirondacks, where coniferous forests
dominate.
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SUMMER:
The months of June, July, and August are delightful
in New York. This is the time where people come outside to work in their
gardens, hit the beaches, camp in the mountains. Temperatures are generally
in the 70s and 80s, but 90° plus readings are possible, especially
in metro-New York City. There usually is a sizeable amount of precipitation
in summer, usually from thunderstorms. The storms can be violent, but
tornadoes are not common events.
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Throughout the state, autumn is the time for harvesting fruit,
especially apples (near Lake Ontario) and grapes (Hudson Valley, Long
Island, Finger Lakes, Lake Erie). The modifying effect of large bodies
of water prevents early frosts, which makes this bounty possible.
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AUTUMN:
September is a month of transition in the Northeastern
United States. Temperatures start to cool dramatically, as the length
of daylight drops below 12 hours. The first frosts of the season occur
in the higher elevations, especially in the Adirondacks. This begins the
season of fall foliage, which is spectacular throughout the state. The
peak for vibrant colors varies from late -September in the mountains to late-October
in Southern New York.
Autumn is also harvest time in New York, and farm markets all
across the state do a booming business. Wine tastings and apple cider
are local traditions. In November, snowfall is possible anywhere in the
state, although it usually doesn't last until December.
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Early October
on the Ausable River, near Wilmington in the Adirondacks. Whiteface
Mountain is in the background.
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There are important differences in climate from place to place.
Temperatures are modified by nearness to water, especially on Long
Island which faces the Atlantic Ocean, and, to a lesser extent, the
south and east shores of the Great Lakes. The High Peaks, such as Mt.
Marcy and Whiteface Mountain, have alpine, tundra-like climates. Much
of the state can boast of beautiful Eastern Hardwood Forests (sugar maples,
oaks, beech, and birch). Higher elevations, however, are covered with
evergreens - pines, spruces, and firs. Of course, much of New York was
long ago cleared of forests to make room for agriculture (although many
forests have returned as secondary growth). Dairy farming is common throughout
much of the state, and fruit orchards and vineyards dominate areas near
the Great Lakes, the Hudson Valley, the Finger Lakes, and Long Island.
As places go, New York is a fairly wet. Most places receive
at least 30 inches of precipitation annually,
and it occurs all year round. There are no dry and wet seasons, like
California. Much of the precipitation falls as snow, especially in the
regions south and east of Lakes Ontario and Erie. These are the snow
belts, and some places south of Buffalo or on the Tug Hill Plateau (north
of Oneida Lake) can get 200 inches of white precipitation in a typical
winter. (To learn more about Lake Effect Snow visit the website created
by the National Weather Service at Buffalo:
http://www.wbuf.noaa.gov/lakeffect/indexlk.html ).
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