Anyone here have the latest isomagnetic chart that shows the Texas Gulf
Coast?

Thanks
Joe

Latest by who?

Oil company surveys are the latest but private property. You can get one
from the USGS.

Llyod

"Joe" wrote in message
oups.com...
Anyone here have the latest isomagnetic chart that shows the Texas Gulf
Coast?

Thanks
Joe

"Joe" wrote in message
oups.com
Anyone here have the latest isomagnetic chart that shows the Texas
Gulf Coast?

Thanks
Joe

Why would anyone want one?

To check a compass card and compare variation values maybe.

Joe

"Joe" wrote in message
ups.com
To check a compass card and compare variation values maybe.

Joe

Who lives in that area besides you?
Why would anyone else want one?

3 million people.

Whay would anyone want a compass card? or a isomagnetic chart?

I'm not the only one with a compass, others may want to make sure a
course plotted is a true course.

Joe

You dope!

An isomagnetic map shows lines of constant magnetic field intensity. You
need the gradient map which shows the gradient of the isomagnetic
potentials. You want the lines that go to the north pole right? Not those
closed circles! Please, please tell me you never leave the dock. You are a
hazard to sailors everywhere!

Lloyd Bonafide


"Joe" wrote in message
ups.com...
To check a compass card and compare variation values maybe.

Joe

Lloyd Bonafide wrote:
You dope!

An isomagnetic map shows lines of constant magnetic field intensity.
You
need the gradient map which shows the gradient of the isomagnetic
potentials. You want the lines that go to the north pole right? Not
those
closed circles!

Hey Lloyd A Bonafide idiot,

The secular variations of the Earth's field call for frequent
determinations of the geomagnetic elements at sea. So far, general
world magnetic surveys have of necessity been restricted to the surface
of the Earth. Previous surveys, including those of the Department of
Terrestrial Magnetism of the Carnegie Institution of Washington, have
led to great improvement in our knowledge of the distribution of the
field, especially during the past few decades.

Thanks for the links BTW

Joe



"Joe" wrote in message
ups.com...
To check a compass card and compare variation values maybe.

Joe

http://www.ngdc.noaa.gov/seg/geomag/jsp/IGRF.jsp

http://www.ngdc.noaa.gov/seg/geomag/jsp/IGRF.jsp

http://www.ngdc.noaa.gov/seg/geomag/jsp/IGRF.jsp


"Joe" wrote in message
oups.com...
Anyone here have the latest isomagnetic chart that shows the Texas Gulf
Coast?

Thanks
Joe