1 / 12

Weather and Our Feelings

The Hong Kong Polytechnic University Department of Applied Physics. Weather and Our Feelings. (Author: Ng Wai Fong). Temperature and thermal feelings. What does the temperature in weather report refer to? Temperature of Air What is cold/hot? The feelings of human on temperature

kermit
Download Presentation

Weather and Our Feelings

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Hong Kong Polytechnic University Department of Applied Physics Weather and Our Feelings (Author: Ng Wai Fong)

  2. Temperature and thermal feelings • What does the temperature in weather report refer to? • Temperature of Air • What is cold/hot? • The feelings of human on temperature • 15℃ = Cold? 35℃ = Hot?

  3. Related Weather Warnings from Hong Kong Observatory Cold Weather Warning –Winter Only Very Hot Weather Warning –Summer Only Is it enough?

  4. Weather and Our Feelings • Factors that influence us on the thermal feelings: • Temperature • Wind Speed • Relative humidity • Radiation of the Sun • Example: • A hot weather with high relative humidity hinder heat loss by the evaporation of sweat, low wind speed will also lower heat loss from human body, thus increasing the level of discomfort.

  5. Heatstroke • Under very hot weather, who are having a greater risk of a heatstroke? Buses without air conditioning pose serious health risks. Bus drivers felt sick and got heatstroke. Standard Chartered Hong Kong Marathon 2010.The heat and humidity sent 55 racers to hospital to be treated for heat stroke or dehydration

  6. Weather and Our Feelings Scientists make use of weather data to estimate human feelings • Thermal comfort (熱舒適度) • The satisfactory level of human towards the coldness/hotness of environment • Eg. Hot, warm, slight warm, neither cold nor hot, just right, slight cool, cool, cold • The condition of the heat exchange between human body and environment • Factors • Temperature • Humidity • Air Current • Hot Radiation • Metabolism • Clothing

  7. Weather and Our Feelings Ways to express the comfort level due to heat: • Net Effective Temperature (NET) • Heat Index (HI)–Summer Only • Humidex (HMI)–Summer Only • Apparent Temperature (AT) • Wind Chill Index (WCI) –Winter • Wet Bulb Globe Temperature Index (WBGT) 2008 Summer Olympics Equestrian Events in Hong Kong

  8. (Activity 1) Calculations:Apparent Temperature AT • AT = Ta + 0.33×e − 0.70×ws − 4.00 where, e = rh / 100 × 6.105 × exp ( 17.27 × Ta / ( 237.7 + Ta ) )

  9. (Activity 1) Calculations:Apparent Temperature AT • AT = Ta + 0.33×e − 0.70×ws − 4.00 where, e = rh / 100 × 6.105 × exp ( 17.27 × Ta / ( 237.7 + Ta ) )

  10. (Activity 1) Calculations:Apparent Temperature AT • AT = Ta + 0.33×e − 0.70×ws − 4.00 where, e = rh / 100 × 6.105 × exp ( 17.27 × Ta / ( 237.7 + Ta ) )

  11. (Activity 2) Scientific Experiment:Estimating Human’s Feelings on Weather • Refer to the worksheet (Scientific Experiment: Estimating Human’s Feelings on Weather by Ng Wai Fong)

  12. (Activity 3) Investigation on the Wet Bulb Globe Temperature Video: http://www.weather.gov.hk/wservice/cstdi/cstdic.htm Discussions: • What is the use of Wet Bulb Globe Temperature (WBGT)? • Why Heat Stress Index is better than other weather information? • Should Heat Stress Index be used and disseminated? • Students can discuss the issues about disseminating Heat Stress Index to the public through a role play with different characters: • Representative of the industrial and commercial sector • Representative of the transport services • Director of the Hong Kong Observatory • School Principal

More Related