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variable and gusty
circulation in the immediate vicinity is
terms leader, flash, and stroke are used when describing
steepest pressure gradient
cyclones, hurricanes, tornadoes
thunderstorms can be associated with these weather activities
what is likely during the mature stage of a thunderstorm?
thunderstorms form when ___, humid air rises in a ___ environment
cumulus, mature, dissipating
three stages of development for t-storms
some of the most dangerous weather is producted why what type of thunderstorm
because of the tremendous pressure gradient associated with a strong tornado, maximum winds approach ___ mph
relatively narrow, elongated bands of thunderstorms that develop in the warm sector of a mid-lat. cyclone
spreading downdraft cuts off air inflow
what causes the dissipating stage of a t-storm?
air-mass contrasts are greatest
why do most tornadoes in the U.S. occur during spring months?
leads to greater instability
why is strong heating of the ground by the Sun associated with t-storms?
atmosphere is most unstable at that time
why are thunderstorms most likely to occur in the afternoon and early evening?
more latent heat is available as energy
why is very humid air near the surface a necessary ingredient for severe thunderstorms?
leading edge of t-storm downdraft
where does a gust front occur?
what shows the motion of precipitation particles?
air mass t-storm is most intense during which stage?
a tornado is a small, very intense example of a ___.
diameter of a typical tornado funnel cloud is
where in the U.S. are t-storms most common?
tornadoes are most frequent during these months
tornadoes most often move toward what direction?
at what time of day is an air-mass t-storm more likely to develop?
________ occurs more than 20 km from the person observing it
percentage of t-storms that produce tornadoes
the Fujita Intensity Scale applies to
downdrafts and updrafts found side by side relate to which stage of a t-storm?
updraft dominance relates to which stage of a t-storm?
if you see lightning and then hear associated thunder 15 sec later, the lightning flash was about ___ mi away.
hurricanes must have sustained wind speeds of at least __ mph
when occurring in the Atlantic Ocean, they are known as hurricanes; what are they known as when occurring in the western Pacific?
what are hurricanes known as that occur in the Indian Ocean?
when a cyclone's strongest winds do not exceed 37 mph, it's called a _____.
what is the single greatest advancement in tools used for observing cyclones?
an announcement aimed at specific coastal areas that a hurricane poses a possible threat generally within 36 hrs is called a ____.
what category of the scale of hurricane intensity is the strongest?
very center of the storm
hurricanes develop most often in the late summer when ocean waters have reached what temperature?
doughnut-shaped wall of intense convective activity surrounding the center of the storm
trade wind inversion
what circumstance may inhibit further development of a hurricane by diminishing air's ability to rise and thus inhibit development of strong t-storms?
general circulation wind belt that is the place of origin for hurricanes
prevailing winds are from the east
why do hurricanes in the Atlantic move toward the west during early stages?
approximate diameter of a mature hurricane
____ determines when a tropical depression is given hurricane status.
sinking air motion
why is the eye region of a hurrcane largely free of precipitation and clouds?
very strong pressure gradient force
what causes the winds of a hurricane to be so fast?
maximum winds likely to exist in a hurricane
friction and lack of warm, moist air
when a hurricane moves onto land, it declines in intensity; what factor(s) contribute to this loss of punch?
which part is a hurricane is warmest?
the greatest number of hurricane-related deaths may be attributed to ____.
during what time of year should hurricane formation in the North Atlantic be at a peak?
scale used to establish categories of hurricane intensity
as a strong hurricane moves ashore, what causes the most devastating damage in the coastal zone?
hurrcanes form between ___° and ___° latitude
to officially be a hurricane, the disturbance must have rotary circulation and have wind speeds of at least ___ km/hr
tropical depression, tropical storm, hurricane
proper order of storm intensity in terms of increasing wind speed
moving over land
what can diminish the intensity of a hurricane?
1 & 2
which scale numbers of hurricanes do only minimal or moderate damage?
which country has historically proven most susceptible to large losses of life from storm surge in the 20th century?
National Weather Service
in the U.S., the governmental agency responsible for gathering and disseminating weather-related information is the ______.
heat waves cause about ___ deaths annually in the U.S.
t-storms and tornadoes
the Storm Prediction Center in Norman, OK maintains a constant vigil for
Washington D.C., Moscow, and Melbourne
3 World Meteorological Centers that compile data and send it to participating countries if the World Meteorological Organization are located near
process of predicting the future state of the atmosphere is called
technique used to attempt to match current conditions with similar well-established patterns from the past
determining the occurrence of precipitation, the NWS forecasts are correct more than ___% of the time
these satellites were placed in orbit over the equator and remain fixed over a point on Earth because they keep pace with the earth's rate of rotation
these satellites circle the earth in a N to S direction & obtain images of the entire Earth twice a day by drifting about 15° westward over the earth's surface during each orbit
infrared images provide a way to determine which type of clouds of more probable
west to east
when upper-air flow produces large amplitude waves and a general ____ flow, mild temperatures and few cyclonic disturbances are experienced south of the jet stream
north to south
when upper-air flow produces large amplitude waves and a general ____ flow, cold air moves southward and cyclonic activity dominates
accuracy of day to day weather forecasts for periods beyond ___ days is relatively unreliable
a weather map shows the status of the atmosphere and includes data on temperature, humidity, airflow, and ____.
cold air moving south
wave pattern in the upper-level winds at mid latitudes provides for
forecasts for regional weather systems (those affecting several states) are prepared by
path that cyclonic storms follow (storm track) is usually farther to the south during
strongly influences development of surface storms
why is the pattern of upper-level winds an important part of the forecasting process?
their orbital motion matches the earth's rotation
why are some satellites describes as being stationary?
accuracy of weather forecasts begins to decrease rapidly for periods greater than
temperature and precipitation
long range forecasts (monthly or seasonal) include predictions of
was measured at the same time
synoptic charts display weather data that
what is NOT plotted on a weather chart
what weather data is not always plotted in the same location with respect to the weather station?
a weather analyst
job of collecting, compiling, and displaying weather data is done by
too many variables to math
major drawback of the analog method of weather forecasting
prediction of future weather data
weather analysis does not include
synoptic charts have isobars plotted at ___ millibar levels
upper-air charts are NOT commonly drawn for ___ millibars
makes extensive use of radar and geostationary satellites
most tragic air pollution episode occurred in London in 1952. more than ___ people died
category of air pollutants is emitted directly from identifiable sources and pollutes the air immediately upon being emitted
smog is an example of a ____ pollutant
source of primary pollutants - accounts for half of our pollution
general term used for a mixture of solid particles and liquid droplets found in air
important sources of ___ include power plants, smelters, petroleum refineries, and pulp and paper mills
volatile organic compounds
encompasses a wide array of solid, liquid and gaseous substances that are composed exclusively of hydrogen and carbon
exposure to this primary pollutant is associated with damage to the nervous systems of young children
most abundant primary pollutant
many reactions that produce secondary pollutants are triggered by ____ and are called photochemical reactions
although ___ forms naturaly in the stratosphere, when produced near the surface, it is considered a pollutant with many negative effects
the Environmental Protection Agency
in the 1970s, the federal Clean Air Act made major strides in reducing air pollution and created
particulates, sulfur dioxide, carbon monoxide, nitrogen oxide, lead and ozone
6 pollutants that are known as criteria pollutants and are covered by the National Ambient Air Quality Standards
strong and variable (gusty)
spreading or dilution of pollutants into the atmosphere is best when winds are
a near total lack of mixing
inversions represent a hazardous meteorological condition with respect to air pollution because they always bring
spread out horizontally but not mix up or down
smoke released from a stack into a very subtle air mass would tend to
reduce the concentration of pollutants at ground level
primary purpose of a smokestack is to
air is unstable
dilution or mixing of air pollutants into the surrounding air is best when
determine the amount of dilution
meteorological conditions are important in air pollution episodes since they
near the center of an anticyclone
air pollution is likely to be most severe
dispersion of pollutant material into the atmosphere depends on the wind and ___ of the air layer
sulfuric acid is a ___ pollutant
source category responsible for the most pollution
major component of photochemical smog
single greatest air pollutant by weight
during what part of the day should ozone levels in an urban environment be highest
what triggers a photochemical reaction
how much more acidic is a substance with a pH of 5 than a substance with a pH of 6
natural source of pollutants not accentuated by humans
regarding air pollution disasters discussed, ___ suffered the most
current axial tilt of earth
burning of coal and petroleum
most important cause of the increase in atmospheric CO2
what helps explain the present cycle of the seasons
reduce solar energy at Earth's surface
volcanic eruptions can act as agents for climate change because they
most likely explanation for evidence of glacial activity in places such as Africa and Australia
oxygen isotope measurements are made from analysis of
remains of living organisms
sea floor sediments provide useful climate data because they contain
drought in the western U.S.
extensive tree ring research indicates that 22 yr sunspot cycle may be related to
higher evaporation rates and decreased rainfall in some areas
possible consequences of a CO2 induced climate change
atmosphere's CO2 content is rising - what is a significant contributor
which gas may be contributing to a greenhouse warming
combustion of coal and oil is major source of which greenhouse gas
possible consequence of greenhouse warming
shifts in paths of large-scale cyclonic storms
possible consequence of greenhouse warming
cryosphere, atmosphere, lithospere
climate system consists in part of
ice and snow
cryosphere consists of
large plates that make up the outer portion of earth move about a few ___ per year
can serve as condesation nuclei
sulfur dioxide aerosols
has risen about 10cm over the last 100 yrs
studies have shown that sea-level
sunspot activity tends to follow a cycle of roughly
the Canadian archipelago
ET climates are found in
closely linked to the location of major pressure and wind systems
on a windward coast
for a continental area to experience a marine type climate, it must be located
mountain ranges play an important role in determining climates because of their influence upon
latitude of a place is important for its climate because it determines
whether evaporation exceeds precipitation
primary factor which determines whether a place will have a dry climate is
temperature and precipitation
what pair of elements is most important in climatic description
four of the five major climatic groups have temperature characteristics as their basis... which does not?
daily temperature ranges usually exceed the annual temperature ranges in
a summer maximum precipitation
most places having an Aw climate experience
vegetation associated with the Aw climate is
approximately ___% of the earth's land surface is desert
rainfall would be most reliable in which climate
migration of the ITCZ
most important factor controlling the seasonal distribution of precipitation in the Aw (tropical wet and dry) realm
the influence of the subtropical highs
deserts such as the Sahara exist because of
which continent is the marine west coast climate most extensive
dry-summer subtropical climate is A.K.A.
low temperatures mean only small loss to evaporation
although subarctic and tundra climates generally have small precipitation totals, they are considered humid. why?
mediterranean climate (Csa & Csb)
only humid climate that has strong winter precipitation maximum
in humid continental climate, shifts in wind directions sometimes cause rapid and large temperature changes. during what season would this be most pronounced?
another name for taiga
supports some plant life but no trees
mean monthly humidity
the Kumlaut(o)ppen classification does NOT use
most important determinant of temperature overall
great diversity of plan species
tropical rainforest is characterized by
climate type that covers the largest amount of earth's land
this climate sees significant rainfall throughout the year
this climate loses much solar radiation heat to reflection and ice melting