ATM OCN 100 Summer ATM OCN 100 – Summer 2002 LECTURE 5 (con’t.) AIR TEMPERATURE: A Fundamental Weather Element u A. Background & Definitions u B. Thermometry u C. Near-surface air temperature climatology
MADISON’S CURRENT WEATHER Madison Weather at 1000 AM CDT MON 24 JUN 2002 Updated twice an hour at :05 and :25 Sky/Weather: SUNNY Temperature: 81 F (27 C) Dew Point: 64 F (17 C) Relative Humidity: 56% Wind: SW6 MPH Barometer: 30.11F ( mb)
ATM OCN 100 Summer Current Surface Winds with Streamlines & Isotachs (“iso” = equal & “tach” = speed) H L L H L H
ATM OCN 100 Summer Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar
ATM OCN 100 Summer Current Temperatures ( ° F) & Isotherms (“iso” = equal +”therm” = temperature)
ATM OCN 100 Summer This morning’s low temperatures ( o F)
ATM OCN 100 Summer Yesterday’s high temperatures ( o F)
ATM OCN 100 Summer Yesterday’s High Temperatures ( o F) – ( ) Average High Temperatures
ATM OCN 100 Summer Current Dewpoints ( o F)
ATM OCN 100 Summer Current Apparent Temperatures ( o F)
ATM OCN 100 Summer Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar
ATM OCN 100 Summer CURRENT IR GABRIELLE
ATM OCN 100 Summer Tomorrow AM Forecast Map
ATM OCN 100 Summer Announcements u Homework 1 –Get from our webpage F –Due this Thursday 27 June 2002
ATM OCN 100 Summer LATEST RADAR
ATM OCN 100 Summer
17 Current Surface Weather Map with Isobars (“iso” = equal & “bar” = weight), Fronts and Radar
ATM OCN 100 Summer Today is the Summer Solstice See Fig Moran & Morgan (1997)
ATM OCN 100 Summer Earth’s Orbit of Sun – The Cause of the Seasons See Fig Moran & Morgan (1997)
ATM OCN 100 Summer Today is the Autumnal Equinox See Fig Moran & Morgan (1997)
ATM OCN 100 Summer
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23 Track of Tropical Storm Helene
ATM OCN 100 Summer Surface Weather Map from Today with Isobars & Fronts
ATM OCN 100 Summer Forecast Weather Map for Tomorrow Morning
ATM OCN 100 Summer Current Temperatures ( o F) & Isotherms
ATM OCN 100 Summer Current Temperatures ( o F) – 24 Hrs Ago
ATM OCN 100 Summer Last 24 hrs in Madison
ATM OCN 100 Summer ATM OCN Summer 2002 LECTURE 5 AIR TEMPERATURE: A Fundamental Weather Element u A. BACKGROUND –Why do we want to know air temperature? – Meteorological Significance of Temperature F A measure of energy of atmosphere – Human Significance of Temperature F Humans are warm blooded; F Humans maintain a constant temperature.
ATM OCN 100 Summer THE DEFINITIONS u TEMPERATURE – A measure of “heat intensity” of object. – Proportional to average energy of motion of individual molecules; or to average molecular speed. u HEAT – A form of energy; – Proportional to total amount of thermal energy found in object.
ATM OCN 100 Summer B. THERMOMETRY u The Science of Thermometry – Measuring temperature. u Types of Thermometers – Liquid-in-glass thermometers – Deformation thermometers – Electrical thermometers – Radiation thermometers (radiometers) where... where...
ATM OCN 100 Summer LIQUID-IN-GLASS THERMOMETERS u Concept: – Volume of fluid (Liquid mercury or alcohol) proportional to temperature; – Measure expansion of liquid in sealed tube.
ATM OCN 100 Summer LIQUID-IN-GLASS THERMOMETERS (con’t.) u Special Recording Thermometers – Maximum recording thermometers (Mercury thermometers) – Minimum recording thermometers (Alcohol thermometers)
ATM OCN 100 Summer Maximum-Minimum Thermometers
ATM OCN 100 Summer DEFORMATION THERMOMETERS u Concept: – Length of material (e.g., metal) proportional to temperature; – Deflection of material monitored.
ATM OCN 100 Summer DEFORMATION THERMOMETERS u Example: – Bimetallic Thermometer; – Used in Thermostats & Thermographs.
ATM OCN 100 Summer ELECTRICAL THERMOMETERS u Concept: – Electrical resistance of material proportional to temperature; – Measure electric current. u Example: – Thermistor; – Used in radiosondes & automatic weather stations.
ATM OCN 100 Summer A Radiosonde
ATM OCN 100 Summer Thermistor on Radiosonde
ATM OCN 100 Summer Thermal Sensor at ASOS
ATM OCN 100 Summer RADIATION THERMOMETERS u Concept: – “Heat Radiation” from material proportional to object’s temperature; – Measure emitted radiation. u Example: – Radiometer; – Used on-board satellites.
ATM OCN 100 Summer Temperatures Retrieved from Infrared Satellite Imagery
ATM OCN 100 Summer Example of Satellite-Based Radiometers: Current Sea Surface Temperatures from SSEC
ATM OCN 100 Summer THERMOMETRY [con’t.] u Measurement requirements – Standard instruments – Thermometer Exposure – Standardized observations
ATM OCN 100 Summer Surface Weather Station
ATM OCN 100 Summer Inside an Instrument Shelter
ATM OCN 100 Summer Automated NWS-FAA Surface Weather Station
ATM OCN 100 Summer Thermal Sensor at ASOS
ATM OCN 100 Summer THERMOMETRY [con’t] u Temperature Scales – Historical Background – The Fahrenheit, Celsius and Kelvin Scales – Temperature Scale Conversions where...
ATM OCN 100 Summer THERMOMETRY [con’t] u Temperature Scales – Historical Background F Need at least 2 reproducible points – The Fahrenheit, Celsius & Kelvin Scales
ATM OCN 100 Summer Reproducible Reference Temperature Points See Fig 4.3 Moran & Morgan (1997)
ATM OCN 100 Summer Temperature Scales Fig. 3.1 Moran & Morgan (1997)
ATM OCN 100 Summer TEMPERATURE SCALES (con’t.) u Relationships:
ATM OCN 100 Summer TEMPERATURE SCALES (con’t.) u Converting Fahrenheit to Celsius
ATM OCN 100 Summer TEMPERATURE SCALES (con’t.) u Converting Celsius to Fahrenheit
ATM OCN 100 Summer TEMPERATURE SCALES (con’t.) u Converting Celsius to Kelvin u Converting Kelvin to Celsius
ATM OCN 100 Summer C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE u Temporal Variation in Air Temperature – diurnal cycle (afternoon maximum vs. sunrise minimum) – annual cycle (summer maximum vs. winter minimum)
ATM OCN 100 Summer January Temperatures - Madison, WI ( )
ATM OCN 100 Summer July Temperatures - Madison, WI ( )
ATM OCN 100 Summer Sample Meteorogram for Madison, WI
ATM OCN 100 Summer Last 24 hours for Madison, WI
ATM OCN 100 Summer Last 24 hours for Madison, WI
ATM OCN 100 Summer
64 C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE u Temporal Variation in Air Temperature – diurnal cycle (afternoon maximum vs. sunrise minimum) – annual cycle (summer maximum vs. winter minimum) u Spatial Variation in Air Temperature – north-south (polar vs. tropical) – land-ocean (continental vs. maritime)
ATM OCN 100 Summer
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68 This morning’s low temperatures ( o F)
ATM OCN 100 Summer Yesterday’s high temperatures ( o F)
ATM OCN 100 Summer Yesterday’s High Temperatures ( o F) – ( ) Average High Temperatures
ATM OCN 100 Summer C. THE CLIMATOLOGY of NEAR- SURFACE AIR TEMPERATURE (con’t.) u Average Daily Temperatures & Degree-Day Units – Background – Types of Degree-Day Units F Heating Degree-Day Units F Cooling Degree-Day Units F Growing Degree-Day Units – Degree-Day Units Computations (where...)
ATM OCN 100 Summer From NOAA: Climate Prediction Center
ATM OCN 100 Summer
75 DEGREE-DAY CALCULATIONS u Calculate daily average temperature & then Heating Degree-Day Units:
ATM OCN 100 Summer HEATING DEGREE-DAY CALCULATION u If T max = 40 o F and T min = 30 o F, then:
ATM OCN 100 Summer Annual Heating Degree Day Units See Fig. 3.11A Moran & Morgan (1997) Point Barrow: 19674
ATM OCN 100 Summer DEGREE-DAY CALCULATIONS u Calculate daily average temperature & then Cooling Degree-Day Units:
ATM OCN 100 Summer COOLING DEGREE-DAY CALCULATION u If T max = 80 o F and T min = 60 o F, then:
ATM OCN 100 Summer D. VARIATION OF OBSERVED AIR TEMPERATURE WITH HEIGHT u Temperature lapse rates – Rate of temperature decrease with height – Units: Celsius degrees per 1000 meters or Fahrenheit degrees per 1000 feet u Layer nomenclature – lapse – inversion – isothermal where... where...
ATM OCN 100 Summer LAPSE CONDITIONS Temperature decreases with height
ATM OCN 100 Summer INVERSION CONDITIONS Temperature increases with height
ATM OCN 100 Summer ISOTHERMAL CONDITIONS Temperature remains constant with height
ATM OCN 100 Summer RADIOSONDE LOCATIONS
ATM OCN 100 Summer GREEN BAY RADIOSONDE SOUNDING TUES AM
ATM OCN 100 Summer TALAHASSEE RADIOSONDE SOUNDING TUES AM
ATM OCN 100 Summer U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997)
ATM OCN 100 Summer VERTICAL TEMPERATURE VARIATIONS (con’t.) The temperature spheres See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause
ATM OCN 100 Summer U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere
ATM OCN 100 Summer VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses” u Reasons for vertical temperature structure u Implications of vertical temperature structure
ATM OCN 100 Summer ppmv = %
ATM OCN 100 Summer VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Temperature Spheres – Troposphere – Stratosphere – Mesosphere – Thermosphere
ATM OCN 100 Summer VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses”
ATM OCN 100 Summer U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause
ATM OCN 100 Summer VERTICAL TEMPERATURE VARIATIONS (con’t.) u The Standard Reference Atmosphere – The Temperature “Spheres” – The boundaries or “pauses” u Reasons for vertical temperature structure u Implications of vertical temperature structure
ATM OCN 100 Summer U.S. STANDARD ATMOSPHERE See Fig. 1.9 Moran & Morgan (1997) Troposphere Stratosphere Mesosphere Thermosphere Tropopause Stratopause Mesopause
ATM OCN 100 Summer RADIOSONDE LOCATIONS
ATM OCN 100 Summer GREEN BAY RADIOSONDE SOUNDING TUES AM
ATM OCN 100 Summer TALAHASSEE RADIOSONDE SOUNDING TUES AM
ATM OCN 100 Summer GREEN BAY RADIOSONDE SOUNDING Monday PM
ATM OCN 100 Summer GREEN BAY RADIOSONDE SOUNDING Tuesday AM
ATM OCN 100 Summer ANCHORAGE RADIOSONDE SOUNDING Monday PM
ATM OCN 100 Summer
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ATM OCN 100 Summer See Fig Moran & Morgan (1997)