CH.2 FIRE WEATHER- FIREFIGHTER'S
HANDBOOK ON WILDLAND
FIREFIGHTING 4th ED.
WHAT LAYER OF ATMOSPHERE IS LOWEST TO THE GROUND AND CONTAINS
ALL OF THE EARTH'S WEATHER PHENOMENA? - answer TROPOSPHERE
WHAT TWO COMPONENTS OF THE EARTH'S ATMOSPHERE ARE MOST
IMPORTANT TO WILDLAND FIREFIGHTING? - answer WATER VAPOR AND
OXYGEN
WHAT IS CONSIDERED NORMAL ATMOSPHERIC PRESSURE AT SEA LEVEL (IN
POUNDS)? - answer14.7
WHERE ARE YOU LIKELY TO FIND THE HIGHEST ATMOSPHERIC PRESSURE? -
answer LOWER ELEVATIONS HAVE HIGHER PRESSURE, SEA LEVEL IS THE
HIGHEST PRESSURE
A BAROMETER IS USED TO MEASURE: - answerTHE RELATIONSHIP BETWEEN
HIGH AND LOW PRESSURE AREAS AND THE MOVEMENT OF AIR WITHIN THEM
ALL OTHER THINGS BEING EQUAL, IN WHAT TYPE OF AREA WILL SOLAR
ENERGY HEAT THE SURFACE TO A HIGHER DEGREE? - answerPLOWED FIELDS
OR BARREN AREAS @115 BECAUSE OF DARK COLOR, TEXTURE, AND LACK OF
SHADE/TRANSPARENCY> GRASS ON THE SOUTH> FOREST/HEAVY
VEG>WATER COVERED AREAS
THE GREATEST AMOUNT OF HEAT IS LOST AT NIGHT WHEN: - answerTHERE IS
NO CLOUD COVER AND THE AIR IS RELATIVELY DRY
WHAT WEATHER FACTOR HAS THE GREATEST IMPACT ON FIRE BEHAVIOR? -
answerWIND
WHAT IS THE RELATIONSHIP BETWEEN WIND AND TOPOGRAPHY? -
answerTOPOGRAPHY CAN CHANGE WINDS DIRECTION AND SPEED
WHAT GENERALLY WILL OCCUR WITH WINDS AS A COLD FRONT
APPROACHES? - answerWINDS WILL SHIFT AND INCREASE IN SPEED, MORE SO
THAN A WARM FRONT
, HOW CAN WILDLAND FIRE ITSELF AFFECT THE WIND? - answerCAUSES LOCAL
AIR CURRENTS THAT ADD THE EFFECT OF PREVAILING WIND ON FIRE
SPREAD, AIR ABOVE THE FLAME BECOMES HEATED AND RISES, GIVING FRESH
AIR ROOM TO COME IN ON THE SIDES, INCREASING THE FIRE INTENSITY
WHAT ARE GENERAL WINDS? - answerAFFECT LARGE AREAS, REPORTED IN
DAILY WEATHER FORECASTS
WHAT IS ONE OF THE WAYS IN WHICH WIND AFFECTS WILDLAND FIRE
SPREAD? - answerINCREASING SUPPLY OF 02 TO AID COMBUSTION, DRIVING
CONVECTIVE HEAT INTO ADJACENT FUELS HASTENING DRYING PROCESS,
INFLUENCING THE DIRECTION OF SPREAD AND SPOTTING, BENDING THE
FLAMES CLOSER TO THE UNBURNED FUELS, PREHEATING DRYING AND
INFIGHTING THEN, CARRYING AWAY MOIST AIR AND REPLACING IT WITH
DRIER AIR, CARRYING BURNING EMBERS TO NEW FUELS AND INCREASING
SPREAD, AND BY MOVING MOISTURE-LADEN AIR THAT MAY REDUCE FIRE
BEHAVIOR.
HOW ARE HIGH AND LOW PRESSURE SYSTEMS CREATED? -
answerATMOSPHERE IS TRYING TO EQUALIZE PRESSURE OF THE AIR CAUSED
BY THE UNEQUAL HEATING OF THE EARTHS SURFACE
WIND SPEED IS DETERMINED BY PRESSURE GRADIENTS, WHILE WIND
DIRECTION IS DETERMINED BY: - answerTHE RELATIONSHIP (LOCATIONS) OF
THE HIGH AND LOW PRESSURE AREAS
WHAT IS THE NAME OF A WARM AIR MASS THAT RIDES UP AND OVER A
COLDER AIR MASS? - answerOCCLUDED FRONT
WHAT ARE EXAMPLES OF LOCAL WINDS? - answerSEA BREEZES, LAND
BREEZES, SLOPE AND VALLEY WINDS. SMALL SCALE CAUSED BY LOCAL
TEMPERATURE DIFFERENCES AND STRONGLY INFLUENCED BY TERRAIN
WHAT IS THE DIFFERENCE BETWEEN SEA BREEZES AND LAND BREEZES? -
answer- SEA BREEZES ARE LIGHT WINDS BLOWING FROM WATER ONTO THE
LAND STARING IN THE MORNING 10-20 MPH AND LOWER FIRE BEHAVIOR
- LAND BREEZES HAVE WINDS GOING FROM THE LAND OUT TO THE SEA
START 2-3 HOURS AFTER SUNSET AND END AFTER SUNRISE AND HAVE
LIGHTER SPEED 3-10MPH
WHAT ARE VALLEY WINDS? - answerWIND CREATED BY SOLAR HEATING, UP
VALLEY (AND SLOPE) WIND START LATE MORNING (10-15MPH). DOWN VALLEY
(AND SLOPE) WINDS START AFTER SUNSET (5-10 MPH)
HANDBOOK ON WILDLAND
FIREFIGHTING 4th ED.
WHAT LAYER OF ATMOSPHERE IS LOWEST TO THE GROUND AND CONTAINS
ALL OF THE EARTH'S WEATHER PHENOMENA? - answer TROPOSPHERE
WHAT TWO COMPONENTS OF THE EARTH'S ATMOSPHERE ARE MOST
IMPORTANT TO WILDLAND FIREFIGHTING? - answer WATER VAPOR AND
OXYGEN
WHAT IS CONSIDERED NORMAL ATMOSPHERIC PRESSURE AT SEA LEVEL (IN
POUNDS)? - answer14.7
WHERE ARE YOU LIKELY TO FIND THE HIGHEST ATMOSPHERIC PRESSURE? -
answer LOWER ELEVATIONS HAVE HIGHER PRESSURE, SEA LEVEL IS THE
HIGHEST PRESSURE
A BAROMETER IS USED TO MEASURE: - answerTHE RELATIONSHIP BETWEEN
HIGH AND LOW PRESSURE AREAS AND THE MOVEMENT OF AIR WITHIN THEM
ALL OTHER THINGS BEING EQUAL, IN WHAT TYPE OF AREA WILL SOLAR
ENERGY HEAT THE SURFACE TO A HIGHER DEGREE? - answerPLOWED FIELDS
OR BARREN AREAS @115 BECAUSE OF DARK COLOR, TEXTURE, AND LACK OF
SHADE/TRANSPARENCY> GRASS ON THE SOUTH> FOREST/HEAVY
VEG>WATER COVERED AREAS
THE GREATEST AMOUNT OF HEAT IS LOST AT NIGHT WHEN: - answerTHERE IS
NO CLOUD COVER AND THE AIR IS RELATIVELY DRY
WHAT WEATHER FACTOR HAS THE GREATEST IMPACT ON FIRE BEHAVIOR? -
answerWIND
WHAT IS THE RELATIONSHIP BETWEEN WIND AND TOPOGRAPHY? -
answerTOPOGRAPHY CAN CHANGE WINDS DIRECTION AND SPEED
WHAT GENERALLY WILL OCCUR WITH WINDS AS A COLD FRONT
APPROACHES? - answerWINDS WILL SHIFT AND INCREASE IN SPEED, MORE SO
THAN A WARM FRONT
, HOW CAN WILDLAND FIRE ITSELF AFFECT THE WIND? - answerCAUSES LOCAL
AIR CURRENTS THAT ADD THE EFFECT OF PREVAILING WIND ON FIRE
SPREAD, AIR ABOVE THE FLAME BECOMES HEATED AND RISES, GIVING FRESH
AIR ROOM TO COME IN ON THE SIDES, INCREASING THE FIRE INTENSITY
WHAT ARE GENERAL WINDS? - answerAFFECT LARGE AREAS, REPORTED IN
DAILY WEATHER FORECASTS
WHAT IS ONE OF THE WAYS IN WHICH WIND AFFECTS WILDLAND FIRE
SPREAD? - answerINCREASING SUPPLY OF 02 TO AID COMBUSTION, DRIVING
CONVECTIVE HEAT INTO ADJACENT FUELS HASTENING DRYING PROCESS,
INFLUENCING THE DIRECTION OF SPREAD AND SPOTTING, BENDING THE
FLAMES CLOSER TO THE UNBURNED FUELS, PREHEATING DRYING AND
INFIGHTING THEN, CARRYING AWAY MOIST AIR AND REPLACING IT WITH
DRIER AIR, CARRYING BURNING EMBERS TO NEW FUELS AND INCREASING
SPREAD, AND BY MOVING MOISTURE-LADEN AIR THAT MAY REDUCE FIRE
BEHAVIOR.
HOW ARE HIGH AND LOW PRESSURE SYSTEMS CREATED? -
answerATMOSPHERE IS TRYING TO EQUALIZE PRESSURE OF THE AIR CAUSED
BY THE UNEQUAL HEATING OF THE EARTHS SURFACE
WIND SPEED IS DETERMINED BY PRESSURE GRADIENTS, WHILE WIND
DIRECTION IS DETERMINED BY: - answerTHE RELATIONSHIP (LOCATIONS) OF
THE HIGH AND LOW PRESSURE AREAS
WHAT IS THE NAME OF A WARM AIR MASS THAT RIDES UP AND OVER A
COLDER AIR MASS? - answerOCCLUDED FRONT
WHAT ARE EXAMPLES OF LOCAL WINDS? - answerSEA BREEZES, LAND
BREEZES, SLOPE AND VALLEY WINDS. SMALL SCALE CAUSED BY LOCAL
TEMPERATURE DIFFERENCES AND STRONGLY INFLUENCED BY TERRAIN
WHAT IS THE DIFFERENCE BETWEEN SEA BREEZES AND LAND BREEZES? -
answer- SEA BREEZES ARE LIGHT WINDS BLOWING FROM WATER ONTO THE
LAND STARING IN THE MORNING 10-20 MPH AND LOWER FIRE BEHAVIOR
- LAND BREEZES HAVE WINDS GOING FROM THE LAND OUT TO THE SEA
START 2-3 HOURS AFTER SUNSET AND END AFTER SUNRISE AND HAVE
LIGHTER SPEED 3-10MPH
WHAT ARE VALLEY WINDS? - answerWIND CREATED BY SOLAR HEATING, UP
VALLEY (AND SLOPE) WIND START LATE MORNING (10-15MPH). DOWN VALLEY
(AND SLOPE) WINDS START AFTER SUNSET (5-10 MPH)
