Chapter_3_Variable_Weather_and_Changing_Climate_-_A_Continuing_Challenge_

GATEWAY 1: Why do different places experience different weather and climate? What is the difference between weather and climate? Weather Climate ● The specific conditions of the atmosphere of a particular place and time ● Shows the short term conditions of the atmosphere. ● Varies from time to time and place to place ○ For example, Singapore on 1st May 2016 at 10 am, hot and sunny but at 4pm raining heavily. ● The average weather conditions of the atmosphere over a long period of time, at least 30 years. ● Climate is what people expect to experience year after year. ○ Places with high temperatures and high rainfall experiences hot wet climate. ○ A place with high temperature in summer and low temperature in winter experiences temperate climate. Elements of weather ● Temperature ​ which is measured with a thermometer. ● Relative humidity ​ which is measured using a sling psychrometer and a relative humidity table. ● Clouds ​ which are measured with your eyes, obviously. ● Rainfall ​ which is measured using a rain gauge. ● Air pressure ​ which is measured using a barometer. ● Wind ​ which is measured using an anemometer. Temperature ● Temperature ​ is the degree of heat or coldness of a place. ● It is measured in ​ Celsius or Fahrenheit ​ scale. ● It is measured using an ​ analogue or digital thermometer, ​ although a ​ maximum and minimum thermometer ​ can be used too. Temperature calculation ● Mean daily temperature ​ is the sum of hourly temperatures divided by 24 hours. ● Diurnal temperature range ​ is the difference between maximum and minimum temperatures recorded in a day. ○ Maximum daily temperature - Minimum daily temperature ● Mean monthly temperature ​ is the average of the daily temperatures in a month ● Mean annual temperature ​ is the average of the monthly temperatures recorded in a year ● Annual temperature range ​ is the difference between maximum and minimum mean monthly temperatures recorded in a year. Factors affecting temperature ● Latitude (Angle of Incidence) ○ Latitude is the distance of any point on the earth measured north or south of the equator. ○ Nearer to the equator, the angle of incidence is higher/vertical and the sun rays are more vertical. ○ This causes solar energy to be concentrated into a smaller area and thus, the temperature will be higher. ○ The opposite is true for areas further away from the equator, causing those areas to have a lower temperature. ● Latitude (Curvature of the Earth) ○ At lower latitudes because of the curved shape of the earth’s surface, the sun rays travel through a shorter distance in the atmosphere. ○ There is less solar radiation lost by reflection, scattering and absorption. ○ Thus places near equator will have higher temperatures as less energy is lost to these processes. ● Altitude (Distance from the surface) ○ The sun emits short wave radiation which is abs