Weather Radar - PowerPoint PPT Presentation

1 / 7
About This Presentation
Title:

Weather Radar

Description:

Weather Radar. John Harris - Head of Geography - Radley College. mjh_at_radley.org.uk ... Weather radar detects echoes from water droplets in rain clouds. ... – PowerPoint PPT presentation

Number of Views:187
Avg rating:3.0/5.0
Slides: 8
Provided by: Dept117
Category:
Tags: radar | uk | weather

less

Transcript and Presenter's Notes

Title: Weather Radar


1
Weather Radar
John Harris - Head of Geography - Radley
College mjh_at_radley.org.uk http//
atschool.eduweb.rmplc.co.uk/radgeog
2
What is radar?
Radar radio detection and ranging
  • Electro-magnetic waves are sent out.
  • Signals (echoes) bounce back from targets eg
    rain droplets.
  • This can show the distance, size and velocity of
    the targets.
  • Weather radar detects echoes from water droplets
    in rain clouds.
  • Computer software processes and maps the data.

3
National radar networks
Many countries have set up weather radar networks
to help weather forecasting and rainfall
prediction.
4
Radar maps
Can you identify the country?
5
What do radar maps show?
Larger droplets have higher radar reflectivity
values (dBZ). These dBZ values can be mapped with
different colours. Data can also be mapped as
rainfall rates - mm per hour. Several images can
be looped to make radar movies.
Radar Reflectivity (dBZ) Type of
precipitation Rainfall rate 0-30 dBZ Light
rain up to 3 mm/hr 30-45 dBZ Moderate
rain 3-25 mm/hr 45-55 dBZ Convective
storm 25-100 mm/hr 55 dBZ Severe storm 100
mm/hr
6
Hawaii radar
Where is the rain mainly falling? How much rain
is falling (mm per hour)?
7
Japan radar - forecast
A band of rain can be seen to the west of
Japan. Question Assuming a westerly wind what is
your forecast for Japan over the next few hours?
Answer wet and windy!
Write a Comment
User Comments (0)
About PowerShow.com