2y ago
721.10 KB
7 Pages
Last View : 15d ago
Last Download : 4m ago
Upload by : Milo Davies

oundWarm air risesAir cools and water vapour condenses to form storm cloudsHeavy precipitationRELIEF RAINFALLe.g. LAKE DISTRICT/PENNINES (York in Rainshadow)(happens when moist air rises over hills and mountains), wet, onshore winds reach a mountain barrier, air is forced to riseAir cools and condenses to form cloudsPrecipitation occurs on the hills/mountainsDry air descends and warms up – clouds evaporateRain shadow – air is dry so very little rain fallsFRONTAL RAINFALLe.g. ACROSS GB IN ‘LOW PRESSURE SYSTEMS‛(happens when warm air and cool air meet) air mass is less dense than cool air – rises over cool air massCool air mass undercuts warm air massAir cools and water vapour condenses to form cloudsPrecipitation occurs

ANTICYCLONES and DEPRESSIONSWeather components interact to produce weather systems called anticyclones and depressions.ANTICYCLONESAnticyclones are cool, dry air massesBecause the air is cool, it slowly sinks creating high pressure.Air sinks – as it sinks it warms – warm air holds more water vapour – clouds unlikely to form.Summer Anticyclones – light winds, sunshine and high temperatures.Winter Anticyclones – light winds, sunshine, low temperatures and frost.Winds blow clockwise in Northern Hemisphere (anticlockwise in Southern).DEPRESSIONSDepressions are areas of low pressure formed when a warm air mass and cool air mass meet.Warm air rises over cool air to form a warm front.Cool air undercuts warm air from behind to form a cold front.Warm air rises along both fronts, cools, condenses and forms rain.An occluded front is formed when warm air is completely undercut by the cool air.Air rises at the centre of a depression and draws in anticlockwise winds (in Northern Hemisphere).The lower the air pressure, the faster the winds.LOWS BRING A DEFINITE SERIES OF WEATHER CONDITIONS1. a low approaches, it starts to drizzle and then rains more heavily as the warm front approaches.When the warm front passes, the rain stops, the weather becomes brighter, the clouds disappear and the temperature rises, dueto being in the warm sector. The cold air behind the cold front moves faster than the warm air, and often overtakes andundercuts the warm sector, giving an occluded front – no warm sector but a longer period of continuous rainfall.About 12 hours on, it gets windier and colder and clouds build up as the cold front moves in.Heavy rain starts to fall and there‛s cold, and windy weather for the next few hours.After the rain, conditions may settle for a short while before the next low or high-as the cold front passes the wind changesdirection (veers) from warm southerly to cool north-westerly.

FACTORS AFFECTING CLIMATEClimate is the average weather of a place based on data recorded over a 30-year period.LATITUDEis how far north or south a place is from the equator – a major influence on temperature and precipitation.ALTITUDEis the height above sea level – the higher a place is the colder and wetter it will be.DISTANCE FROM SEAPlaces that are influenced by sea temperatures have a maritime climate – wet with a small temperature range.Places inland that are not influenced by sea temperatures have a continental climate – dry with a large temperature range.PREVAILING WINDare the most frequent winds affecting an area – they influence temperature and precipitation.Sea Winds bring precipitationLand Winds bring dry weatherPolar Winds bring cold weatherTropical Winds bring warm/wet weather and precipitationOCEAN CURRENTSWarm Ocean Currents flowing from the tropics towards the poles warm the surrounding area, especially in winter (see below)Cold Ocean Currents usually have less effect, but may lower temperatures and cause fog.ASPECTis the direction a place faces. On a local scale aspect is very important. In the British Isles south facing places are warmer than north andeast facing places.

MICROCLIMATESA Microclimate is where there are local differences in climatic featuresAspect is the direction in which a placefaces. Places that face the sun arewarmer than those in shadow. In theUK places with a south-facing aspectget more sun and higher temperaturesGround surface can influence the localclimate. Dark, artificial surfaces, liketarmac, warm up faster and give offmore heat than light, natural surfaces,like grassWalls, buildings and trees provideshelter from windTrees provide shade and shelter andare usually cooler than surroundingareas. Water areas such as lakes andseas have a cooling effect and may alsoproduce light winds. Hill tops areusually cool and windyBuildings can change the wind speedand direction, creating some areas ofcalm and other areas that are windy.On warm sunny days buildings absorbheat and, later, give it off. Night-timetemperatures in cities can be 2-3 Cwarmer than surrounding areas

Warm air rises over cool air to form a warm front . Cool air undercuts warm air from behind to form a cold front . Warm air rises along both fronts, cools, condenses and forms rain. An occluded front is formed when warm air is completely undercut by the cool air.

Related Documents:

6/30/2019 1 Physical Geography: Weather and Climate Chapter 4 Weather vs. Climate Weather –short-term, day-to-day expression of atmospheric processes Ex. - Today is clear, cold and sunny Climate –long-term, average conditions Usually at least 30 years of daily weather data (temperatures and precipitation)

Weather instruments are used to measure and record the weather. Weather instruments can be found in weather stations on land. The Met Office has hundreds of weather stations all over the UK. Weather instruments are also found at sea. They are found on some ships, but mainly on weather buoys designed to monitor weather and sea conditions.

weather/climate spectrum. This chapter provides basic information to understand weather, climate, climate variability and climate change, and then discusses some analytical methods used to address the unique challenges presented when study-ing these exposures. CHAPTER 2 Weather and climate:

Weather VS. Climate Climate describes average weather conditions over longer periods and over large areas.Ex : Mediterranean climate (hot dry summer, cool wet winters) Weather describes the day-to-day conditions of the atmosphere. Weather can change quickly - one day it

Weather and Climate 6 2275 Speedway, Mail Code C9000 Austin, TX 78712 (512) 471-5847 www.esi.utexas.edu 6. Compare the weather in your city and the area (climate). Weather Type Your City Area (classroom average) 7. Create a graph showing the weather in your city vs. the climate

Unit 2 Weather 5 LESSON 1 Today’s Weather BIG IDEAS Weather affects the way we live, what we eat and wear and how we feel. We can describe weather conditions by using mathematics. LESSON 2 What Makes Weather? BIG IDEAS The sun heating the earth and its atmosphere causes the weather. We feel weather as wind, heat or cold, and humidity in the form of rain,

Winter Weather Safety Know Your Risk, Take Action, Be a Force of Nature weather.gov/safety. Building a Weather-Ready Nation // 2 NATIONAL WEATHER SERVICE Winter Weather Hazards . Keep an eye out for debris, downed power lines, and tree branches weather.gov/safety. Building a Weather-Rea

Weather instruments Weather data Working definition of weather . 4.1-3 PROCEDURES 1. Have the students work in small groups to make concept maps about weather. Have them Include different kinds of weather, tools used to measure weather, and any other ideas they have about weather.