Pilot's Guide

Garmin G1000 Pilot’s Guide for the Tiger AG-5B 190-00617-00 Rev. A9-12
GDL 69/69A
• The resolution of displayed NEXRAD data is 2 kilo-
meters. Therefore, when zoomed in on the display,
each square block is 2 kilometers. The intensity
level reflected by the square will be the highest level
sampled within the 2 kilometer square area.
NEXRAD Intensity
Colors are used to identify the different NEXRAD
echo intensities (reflectivity) measured in
dBZ
(decibels of Z). “Reflectivity” is the amount of
transmitted power returned to the radar receiver.
Reflectivity (designated by the letter Z) covers a wide
range of signals (from very weak to very strong). So, a
more convenient number for calculations and compari-
son, a decibel (or logarithmic) scale (dBZ), is used. The
dBZ values increase as the strength of the signal returned
to the radar increases.
ECHO TOP – press the ECHO TOP softkey to show
the location, elevation, and direction of the high-
est radar echo. This may not indicate the top of
a storm or clouds, only the highest radar return
echo. The information is derived from NEXRAD
information and indicates the highest altitude at
which precipitation is falling. ECHO TOPS and
Radar coverage are activated at the same time.
ECHO TOPS are mutually exclusive from both
NEXRAD and CLOUD TOPS, that is, when ECHO
TOPS is activated, NEXRAD and CLOUD TOPS
are removed. Refer to the Legend for a descrip-
tion of the ECHO TOPS coding. The update rate
is every 7.5 minutes.
NOTE: Cloud Tops and Echo Tops use the same
color scaling to represent altitude. Turning on
both products at the same time is not allowed.
Opt Equipment_00617-00_0A.indd 12 7/12/2005 8:21:46 AM