TIROS-1: The First Weather Satellite

Geostationary Orbit

GOES Weather Satellite

GOES Weather Satellite

Five geostationary satellites

Polar Orbit Earth rotates under satellite. Satellite sees a narrow swath, about 2000 km wide Roughly twice a day coverage

NOAA Polar Orbiter

Visible Imagery (.5-.7 microns)

Infrared Imagery (typically 10-12 microns)

IR Enhancement Steep Linear Enhancement: Going through a wide range of shades over a limited temperature range Contouring: Discontinuous change of shading at certain temperatures to indicate specific values Color enhancement: Using color to highlight certain temperature values.

MB Enhancement

Fog Product Based on Difference Between IR and SW IR

Water Vapor Channel

Products from the GOES Sounder

19 Channels

GPS Sounding A constellation of GPS satellites orbit the earth. By measuring the delay in time as the GPS signal is bent by the earth’s atmosphere, one can acquire density information that can be used to create temperature and humidity soundings. Can do this with fixed receivers on earth or with receivers on satellites--the COSMIC project.

Cosmic Soundings

The Golden Rule of Satellite Interpretation It is the relative motions of air parcels with respect to each other that is best related to cloud patterns, NOT the motion WRT the earth that is explicitly shown by the wind field.

Thunderstorms

Snow L Can you see the snow pack? Hint: The clouds move, the snow doesn’t. Snowpack L Valley Fog

Visible imagery is analyzed in terms of brightness and texture Visible imagery is analyzed in terms of brightness and texture. Deeper, more vertically developed clouds such as these thunderstorms over the mid Atlantic region appear very bright while lower, thinner clouds are grayer. Also note the very lumpy texture to the convective cloud tops vs nearby stratified clouds along the PA/MD border.

Note the differences in land vs water temperatures in this nighttime IR image. The dark specks are lakes, large rivers and reservoirs. The Great Lakes are also contrasted well against the adjacent cold land mass.

Note sharp, dendritic pattern to this river fog over the MS and lower WI river valleys. Also note the long lived contrails over eastern WI.

A polar orbiter view of valley fog in the Appalachians A polar orbiter view of valley fog in the Appalachians. Note the dendritic pattern produced by topography.

With unstable, cumuliform clouds, wind flow will be parallel to cloud “streets”.

Polar air flowing across the Great Lakes often produces lake effect clouds and snow squalls. What was the direction of wind flow over the upper Midwest on this day?

Look at the overshooting tops boiling up through the anvil canopy of this severe thunderstorm complex. Note also the wavelets in the anvil downstream over AR and MO. These are a good example of gravity waves and are known to be associated with severe turbulence.

A good example of mountain wave turbulence (MWT) as indicated by satellite imagery.

Rope Clouds-Cold fronts