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Meteorology the study of atmospheric phenomena

Meteor means high in the airPrimary types HydrometeorsCloud dropletsForms of precipitationLithometeorsSmoke, haze, and dustElectrometeorslightning

Weather vs. ClimateWeather- The current state of the atmosphere.Short term variations

Climate- Long term variations in the atmosphere.Averaged over 30 years or more.

Words the Weatherman UsesWhat words does the weatherman use to describe the weather?TemperatureTemperature measurement of how rapidly or slowly molecules move around.The faster they are moving, the higher the temperature

What to Wear?If you heard on the news in the morning, Today the high will be 30 degrees how would you dress?

It depends! If you the temperature were in Fahrenheit, you would want to be this young lady

However, if the temperature were in Celsius, you would want to actually be this guy! (30C = 86F!)

And, if the temperature were in Kelvinyou would not be alive! (30 K = -458F)

Moral of this storyalways report in lab what temperature scale you are using!

Temperature versus HeatTemperature and heat are differentHeat -The rate of transfer of energy that occurs because of a difference in temperature between two substancesHeat (or energy) flows from the object with the higher temperature to the object with the lower temperature.

How are heat and temperature different?

The sun is the source of all energy in the atmosphere.This energy is transferred to Earth and throughout the atmosphere in three ways:RadiationConductionConvectionSOLAR FUNDAMENTALS

What is Radiation?Radiation is the transfer of energy through space by visible light, ultraviolet radiation, or other forms of electromagnetic waves.Radiation is named by the length of its wavelength. We only see a very small part of the spectrum. The part we experience as heat is the infra-red portion of the spectrum.

Which of these pictures is of our sun?

X-RaysUltravioletUltravioletVisibleInfraredRadio and MicrowavesEarth is continuously absorbing radiation, but it is also continuously sending it back into space.35% is reflecting back into space; 15% is absorbed by the atmosphere; only 50% is absorbed by the earth.Absorption depends on the physical characteristics of the area and also the amount of solar radiation it receives. For example: Water vs. LandDarker Objects vs. Light ObjectsRADIATION

Solar radiation does not heat the air directly.Solar energy that passes through our atmosphere is in the form of short waves (mostly light waves).Energy that is radiated from the Earth is infra-red radiation. These long waves can not pass through the Earths atmosphere because they are absorbed.This energy is absorbed by the atmosphere and warms the air through the processes of conduction and convection. CONDUCTION AND CONVECTION

Conduction is a type of energy transfer that occurs when molecules collide.It only occurs when molecules are in contact with each other.CONDUCTION

Convection is the transfer of energy by the flow of a heated substance.In the atmosphere, warm air becomes less dense and rises, it then cools and sinks, and the process begins again.These air movements are called convection currents, which are ultimately responsible for weather. CONVECTION

LET US REVIEW:Measuring TemperatureTemperature is measured in three different scales:Fahrenheit (F)32 degrees is freezing, 212 degrees is boiling, -523 is absolute zeroCelsius (C)0 degree is freezing, 100 degrees is boiling, -273 is absolute zeroKelvin (K)273 K is freezing, 373 is boiling, 0 is absolute zero

**Absolute zero is the temperature that the molecules stop moving**Moisture in the AtmosphereHow much water is in this room?

Meteorologists use 2 ways to describe moisture:Dew PointRelative HumidityRelative HumidityHumidity the amount of water vapor in the airRelative humidity the amount of water vapor relative (or compared to) the total amount that the air can holdAir with a higher temperature can hold more water vapor.Relative humidity ranges from 0 to 100 percent. (100 percent = saturated = air has reached the dew point)

Dew PointDew Point the temperature to which air must be cool at constant pressure to reach saturation or the maximum amount of water vapor there can beThe absolute way of measuring how much water vapor there is in the atmosphere is by using the dew point. (A dew point of 70 degrees Fahrenheit has more water vapor than a dew point of 50 degrees Fahrenheit)Condensation occurs at this temperature the water vapor changes into liquid water droplets

Which way of measuring humidity do you think is more helpful?Air Pressure and DensityAir pressure = force exerted by air moleculesPressure is measured in millibars (mb)Pressure decreases as you move up through the atmosphere because there are less and less gas particles exerting pressure

WindWind is the movement of airAir moves from areas of high density to areas of low density to correct the imbalance.Unequal heating of different surfaces causes wind during the day.Wind has a speed and a direction.Speed is in mph or knotsDirection is where is comes from.Reading a Station ModelAll your weather information in one place!

Pressure, Temperature and Density are Related!T = Temperature , P = Pressure, D = Density

T , P , D

T , P , D

Table 11-2 on page 280 in your textbook shows a great summary of this information.