Exam 1

Wien's displacement law says, as the surface temperature of objects increases, the wavelength at which radiation emitted by that surface is most intense

Decreases

Human activities and surface materials combine to produce the urban heat island. The difference in urban/rural temperatures is usually greatest at

Night

Weather forecasts disseminated to the public result from ______ models.

Numerical

Outlooks and statements of potential activity associated with thunderstorms and their hazards are provided by NCEP's ______ Center in Norman, Oklahoma.

Storm prediction

The atmosphere is relatively transparent to solar radiation and relatively opaque to the Earth's infrared radiation. This results in significant ______ of the lower troposphere.

Warming

NWS provides a weather ______ when the hazardous condition is taking place or is imminent.

Warning

The National Weather Service provides a weather ______ when conditions indicate that the relevant hazardous event is possible.

Watch

The transfer of latent heat energy from Earth's surface to the troposphere is of greater magnitude over

Water

The only gaseous component of the atmosphere whose concentration is routinely contained in all weather reports is ______. (Refer to Chapter 1.)

Water vapor

The principal greenhouse gas is

Water vapor

Selected weather-reporting stations are shown on the map as circles. The wind directions at those reporting stations are shown by the line (which can be thought of as an arrow shaft) depicting the air flow into each circle location. In meteorology, wind at a station is identified by the direction from which the air is flowing, i.e., air arriving at the station from the south is called a south wind. Therefore the wind direction at Green Bay, in eastern Wisconsin, at map time was generally from the ________.

West-northwest

In the case of the high, vertical air motion is

downward

Assuming no atmospheric effects, the total amount of solar energy received at a particular location on Earth during one daylight period will be determined by how high the sun rises in the sky (solar altitude) and

length of daylight

The scientific method is a systematic form of inquiry involving

All of these

By employing this sea-level correction, surface weather maps are thus constant _____ maps.

Altitude

The relatively warm layer of the atmosphere in the upper stratosphere and lower mesosphere (average temperature profile graph) is produced by heat-generating chemical reactions involved in the natural formation and dissociation of ozone. The warm layer's maximum temperature of about ______ °C occurs at an altitude near 50 km.

0

To compare air pressures from place to place on the Earth's surface, a reduction-to-sea-level adjustment is made. Consequently, on a surface weather map the assumption is made that for purposes of pressure analysis all stations are located at an altitude of _____ m above sea level.

0

International weather observing utilizes Coordinated Universal Time (UTC), previously "Greenwich Mean Time". 1200 UTC is ______ CST.

0600

Air pressure is equal to the total weight of a vertical column of air with a unit cross-sectional area extending from the place of measurement to the top of the atmosphere. Air pressure at sea level is approximately 14.7 pounds per square inch or approximately _____ kilograms per square centimeter.

1.0

According to the Standard Atmosphere, on average 25% of the atmosphere's mass (25% of pressure) is found above an altitude of approximately _____ km., or, stating it another way, 75% of the atmosphere's mass is found below that altitude.

10

In the United States, meteorologists currently use the millibar (mb) unit as the standard unit of air pressure (equal to a hectoPascal). Standard sea-level air pressure is _____ mb.

1013.25

According to the figures showing the solar illumination on the solstices and equinoxes, the period of daylight at the equator is always the same, that is, ______ hours.

12

According to graph of average temperature profile of the atmosphere, the average temperature at the Earth's surface is about ______ °C.

15

A national weather service for the U.S. was implemented by President Grant in

1870

The beginnings of the worldwide weather observing system was initiated with the founding of the International Meteorological Organization in

1878

Assuming no atmospheric effects, sunlight is most intense on Earth where the noon sun is directly overhead (at the zenith). The noon sun can be at the zenith only at locations within ______ degrees latitude of the equator.

23.5

Air pressure is reported in a variety of units. The air pressure unit most commonly reported to the public is based on the height of a column of mercury which exerts at its base the same pressure as the atmosphere at that place. This pressure measurement technique is adequate for many purposes because the height of the mercury column is directly proportional to air pressure. The average (standard) sea-level atmospheric pressure is ______ inches of mercury. This is equivalent to 76 cm or 760 mm of mercury.

29.92

According to Figure 4.20 showing the latitudinal variation of absorbed solar radiation and emitted infrared radiation, over the period of a year, the Earth receives from space and emits to space equivalent amounts of radiant energy at latitudes of about ______ degrees N and S.

32

Because air pressure is determined by the weight of the overlying air, knowing air pressure values at sea level and at different altitudes makes it possible to determine the amount of atmosphere (by mass) that is above and below a particular altitude. For example, average sea-level air pressure is approximately 1000 mb. At the altitude where the pressure is 500 mb, half of the mass of an atmospheric column would be below and half above. From the Standard Atmosphere Table, this occurs at an average altitude of about _____ km above sea level.

5.5

The basic surface weather observations in the United States are taken by

ASOS

NWS Forecast Offices handle the mix of surface, upper air and satellite observations along with forecast guidance material using computer workstations known as

AWIPS

Cold or warm air advection is likely to be taking place when the winds depicted on a weather map blow ______ isotherms.

Across

The minute liquid and solid particles that are suspended in the atmosphere are known as

Aerosols

In response to temperature gradients, heat is transferred by

All of these

The ideal gas law is a relationship between

All of these

A pressure-sensitive altimeter used in aircraft to measure altitude is a(n) _____ barometer

Aneroid

Because the Earth is neither warming up nor cooling down significantly over time, it follows that the excess radiant energy received at lower latitudes must be transported in the form of heat to higher latitudes to compensate for the net loss of radiant energy at those latitudes. This poleward heat transport is predominantly by ______ processes.

Atmospheric

Global climate change can occur by elevated levels of atmospheric CO2. This theory is the ______ effect.

Calendar

One unit on the Kelvin temperature scale is equal to one degree on the _____ scale.

Celsius

A bold blue "H" has been marked on the map along the Wyoming-Nebraska-Colorado border to denote the general center of high pressure in that area. Compare the hand-twist model of a High to the wind directions at stations in the several-state area near the high-pressure center, particularly from eastern Montana to central Colorado. Wind directions at these stations suggest that, as seen from above, the air spiraled generally ________ around this Northern Hemisphere high-pressure center.

Clockwise

Based on Figure 2, which of the following best describes the surface wind circulation around the center of a high-pressure system (as seen from above)? ______

Clockwise and outward spiral

This wind flow pattern about the High is generally ________ the hand-twist model of a High.

Consistent with

This wind flow pattern about the Low is therefore ________ the hand-twist model of a Low.

Consistent with

This wind flow pattern about the Low is therefore ________ the hand-twist model of a Low. [Refer to Investigation 1B in the AMS Weather Studies Investigations Manual for the hand-twist models of Lows and Highs.]

Consistent with

This wind flow pattern with respect to the High center is generally ________ the hand- twist model of a High.

Consistent with

Of the following heat transfer processes, which one is much more important in transferring heat within the troposphere?

Convection

Ascending, unsaturated air _____ at the rate of 9.8 degrees Celsius per 1000 m.

Cools

A bold red "L" has already been marked on the map along the Minnesota-Wisconsin border to denote the general center of low pressure in that area. Compare the hand-twist model of a Low to the wind directions at stations in the several-state area surrounding the low-pressure center. Wind directions at these stations suggest that, as seen from above, the air was circulating generally ________ around this Northern Hemisphere low- pressure center.

Counterclockwise

A bold red "L" has already been marked on the map in the Great Lakes area near Green Bay to denote the general center of low pressure in that area. Compare the hand-twist model of a Low to the wind directions at stations in the several-state area surrounding the low-pressure center. Wind directions at these stations suggest that, as seen from above, the air spiraled generally ________ around this Northern Hemisphere low-pressure center.

Counterclockwise

Based on Figure 1, which of the following best describes the surface wind circulation around the center of a low-pressure system (as seen from above)? ______

Counterclockwise and inward spiral

Review the Applications portion of Investigation 1A. The Figures 2 and 3 surface weather maps in Investigation 1A from the RealTime Weather Portal were for the same time as this investigation's Figure 3. The Investigation 1A, Figure 3, weather map shows the pressure analysis using isobars. The isobar pattern on the Investigation 1A, Figure 3 map ________ generally depict the positions of the L and the H marked on this activity's Figure 3 map. (Also, if you look at the isobar pattern you drew on Investigation 1A, Figure 2 map, it should reveal those same pressure centers.)

Did

Review the Current Weather Studies 1A. The surface weather maps from Current Weather Studies 1A on the RealTime Weather Portal course website were for the same time as this activity's Figure 1. The CWS 1A, Figure 2, weather map shows the pressure analysis using isobars. The isobar pattern on the CWS 1A, Figure 2, map ________ generally depict the positions of the L and the H marked on this activity's Figure 1 map. (Also, look at the isobar pattern you drew on CWS 1A's Figure 1 map; it should reveal those same pressure centers.)

Did

In a high-pressure system, air flows ______.

Downward and outward in a clockwise spiral

Which of the following two horizontal surfaces open to the atmosphere will warm more quickly on a sunny day?

Dry

The maximum daily temperature is driven by the diurnal radiation budget and usually occurs at

Early afternoon

To optimize the forecast skill of the models, multiple forecasts are created using slightly perturbed beginning conditions to judge the consistency of the results. This process is called ______ forecasting.

Ensemble

Avogadro's Law states that equal volumes of gases (or gas mixtures) measured under the same conditions of temperature and pressure contain _____ number of molecules.

Equal

When a volume of gas expands due to decreasing surrounding pressure, the volume undergoes

Expansion cooling

Surface air pressure will _____ in regions where less air converges at the surface than ascends.

Fall

In the case of the High, the palm of your hand ______ during the rotating motion.

Falls

Forecasting is the result of inputting observational data at a particular time, then using mathematical equations that relate those weather variables on a three-dimensional grid of points. Next the equations project the grid values

Forward in time

The lower the albedo of a surface, the ______ the amount of radiation falling on that surface that is absorbed and converted to heat.

Greater

Refraction or bending of light by atmospheric ice crystals can produce circles about the sun called

Haloes

The subdivision of the atmosphere in which the ratio of nitrogen to oxygen is everywhere constant at about 4 to 1 is known as the

Hemisphere

Because of the great differences in their surface temperatures, the sun radiates most intensely in the visible segment of the electromagnetic spectrum whereas the much cooler Earth radiates most intensely in the ______ segment.

Infrared

The winds at stations around (several state area) the low-pressure center indicated that the air also was spiraling generally ________ the low-pressure center.

Inward toward

The winds at stations near the low-pressure center indicated that the air also was spiraling generally ________ the low-pressure center.

Inward toward

Surface weather maps employ coded station models to display data. Analyses of these maps are routinely done by drawing

Isobars

When liquid water or ice vaporizes or ice melts, heat energy is absorbed from the environment. When water vapor changes directly to liquid or ice, or liquid water freezes, heat energy is released to the environment. The heat energy involved in these phase changes is known as ______ heat.

Latent

Under otherwise similar clear-sky conditions, the less the amount of water vapor in the air the ______ the overnight low temperature.

Lower

Water vapor molecules have less mass than air "molecules". As a result, surface air pressure in a humid air mass would be _____ than that in a dry air mass if their temperatures and other characteristics are the same.

Lower

The interaction of the solar wind with Earth's magnetic field produces the

Magnetosphere

Larger atmospheric particles such as cloud droplets and aerosols scatter wavelength of sunlight more evenly. This is an example of ______ scattering.

Mie

The Automated Surface Observing System consists of sensors, computers and communications ports that can update observations as frequently as each

Minute

With an increase in altitude, air pressure decreases _____ rapidly in cold air than in warm air.

More

A bold blue "H" has been marked on the map in central Colorado to denote the center of high pressure existing in that general area. Note the pattern of wind directions at stations in the several-state area surrounding the high-pressure center. Wind directions at these stations suggest that, as seen from above, the air flowed generally clockwise and spiraled ________ this Northern Hemisphere high-pressure center.

Outward from

The principal source of free oxygen in the Earth's atmosphere is

Photosynthesis

Air is a relatively ______ conductor of heat.

Poor

Worldwide observations are transmitted by the Global Telecommunications System to NOAA's National Centers for Environmental ______ for use in weather, ocean and space forecasting.

Prediction

A radiometer that measures incoming solar radiation intensity is a

Pyrometer

A direct (in situ) atmospheric measurement device would be a thermometer. A remote sensing device would be

Radar

The basic system for taking observations of the atmosphere above the surface utilizes instrument packages with temperature, humidity and pressure sensors that are tracked to infer winds are called

Rawinsondes

Blue wavelengths of sunlight are preferentially scattered by gas molecules in the atmosphere to give the sky its color. This is an example of ______ scattering.

Rayleigh

On your desk, repeat the hand twists for the low- and high-pressure system models. Note the vertical motions of the palm of your hand. For the Low, the palm of your hand ______ during the rotating motion.

Rises

NCEP's Space Weather Prediction Center observes and forecasts solar activity that is important for the operations of the many

Satellites

Photochemical smog is designated a ______ air pollutant.

Secondary

The Antarctic "Ozone Hole" typically reaches maximum size in

September

Knowing the direction from which the wind at Chicago was blowing, it would be reported as a ________ wind.

South - southwest

Selected weather-reporting stations are shown on the map as circles. The wind directions at those reporting stations are shown by the line (which can be thought of as an arrow shaft) depicting the air flow into each circle location that is reporting wind. In meteorology, wind at a station is identified by the direction from which the air is flowing, (i.e., air arriving at the station from the south is called a south wind). Therefore, the wind direction at Chicago, in northeast Illinois, at map time was generally from the ________. [Keep in mind, because of the map projection used, the north direction may not be precisely at the top of the map. In the Chicago area, a north/south line would be nearly parallel to the Illinois-Indiana border segments.]

South - southwest

Given the direction the wind at Green Bay was from, it would be reported as a ________ wind.

South-southwest

The oceans are slow to warm in summer and slow to cool in winter. A principal reason for this is water's unusually high

Specific heat

NCEP's Climate Prediction Center forecasts probability of temperature or precipitation anomalies for areas of the country up to a year in advance by relating ______ with climatic variations such as El Niño or La Niña.

Teleconnections

The Stefan-Boltzmann law relates the total energy flux to the fourth power of a blackbody's

Temperature

The Earth's global temperature, when averaged over time, is quite constant. This is because the planet radiates to space an amount of energy that is ______ the amount it receives from the sun.

The same as

The ultimate source of the energy that drives the atmosphere, produces weather, and is the principal control of climate is the

The sun

Based on the average vertical temperature profile, the atmosphere is divided into four concentric layers. Most weather is confined to the layer called the

Troposphere

Tropical storm and hurricane forecasts provided to the public by the National Hurricane Center display a projected track of the storm center along with a measure of possible variation called the "cone of

Uncertainty

Ultimately, atmospheric circulation and changes in weather arise from ______ rates of radiational heating and cooling within the Earth-atmosphere system.

Unequal

Imagine that the motions of your palms during these rotations represent the directions of vertical air motions in Highs and Lows. Vertical air motion in a Low is therefore ______.

Upward

Considering the complete air motions of the low-pressure system, air flows ______.

Upward and inward in a counterclockwise spiral

Earth's surface is cooled by three processes: radiation, vaporization of water, and conduction plus convection. Of these three cooling processes acting on a global scale, the most important is

Vaporization

Residents of which state are most likely to see an aurora on a clear winter night?

Wisconsin