Weather Instruments & Forecasting Weather was studied at particular locations until the invention of...

Post on 12-Jan-2016

212 views 0 download

Tags:

Transcript of Weather Instruments & Forecasting Weather was studied at particular locations until the invention of...

Weather Instruments & ForecastingWeather was studied at particular locations

until the invention of surface maps (1800s) & aircraftWeather stations spring up around airports

Early 1900s-1960s: weather forecasting based on surface maps

Invention of radar & satellites brought whole new dimension to weather forecastingRadar was the first way we could “see”

precipitationSatellites were the first way we could “see”

storms from outer space

I. Satellite1. Two types:

a. Geostationary - fixed position, can watch a large area 24/7

b. Polar – only take 2 pictures per day (better quality);

closer to Earth

Geostationary vs. Polar-Orbiting Satellites

2. Two modes: a. Visible (VIS) - what we’d see from space Pros - very detailed, can spot cloud

thickness Cons – can’t see at night, can’t distinguish snow from clouds easily

2. Two modes:

b. Infrared (IR) – measure clouds based on temperature Pros - coverage day and night, 24/7

Cons - difficult to spot low clouds (i.e. fog)

High clouds are cold and show up brightly on an infrared image

Low clouds are warm and show up darker on an infrared image

II. Doppler Radar – measures precipitation intensity and coverage; wind speed and direction

•A radar beam shoots a wave of energy out of the tower•The wave bounces off particles like precipitation•Part of the wave returns to the tower

Doppler Radar in Weather Forecasting Doppler Effect Explained

Rain Intensity

Red and Purple Heavy

Orange and Yellow

Moderate

Green and Blues Light

Type of Precipitation

Green Rain

Blue Snow

Pink Freezing Rain/Sleet

White Hail

Using wind speed and direction to recognize tornados

BIRDS!