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<caption><strong> Mercator </strong></caption> <tbody>
<tr>
<th> Element </th>
<th> Contents </th>
<th style="vertical-align: top; text-align: center;">
GRIB API keys<br>
</th>
</tr>
<tr>
<td> 1 </td>
<td> Data representation type (see <a
href="/publications/manuals/d/gribapi/fm92/grib1/show/ctables/">WMO
code table 6</a>); 1 for Mercator </td>
<th style="vertical-align: top; text-align: left;"><a href="/publications/manuals/d/gribapi/keys/grids/">gridType</a>
</th>
</tr>
<tr>
<td> 2 </td>
<td> Number of points along a parallel. </td>
<th style="vertical-align: top; text-align: left;">Ni<br>Nx
</th>
</tr>
<tr>
<td> 3 </td>
<td> Number of points along a meridian. </td>
<th style="vertical-align: top; text-align: left;">Nj<br>Ny
</th>
</tr>
<tr>
<td> 4 </td>
<td> Latitude of the first grid point. </td>
<th style="vertical-align: top; text-align: left;">latitudeOfFirstGridPointInDegrees*1000
</th>
</tr>
<tr>
<td> 5 </td>
<td> Longitude of the first grid point. </td>
<th style="vertical-align: top; text-align: left;">longitudeOfFirstGridPointInDegrees*1000
</th>
</tr>
<tr>
<td> 6 </td>
<td>
<pre>Resolution flag:<br> 0 Direction increments are not given.<br> 128 Direction increments are given.<br></pre>
</td>
<th style="vertical-align: top; text-align: left;">ijDirectionIncrementGiven*128
</th>
</tr>
<tr>
<td> 7 </td>
<td> Latitude of the last grid point. </td>
<th style="vertical-align: top; text-align: left;">latitudeOfLastGridPointInDegrees*1000
</th>
</tr>
<tr>
<td> 8 </td>
<td> Longitude of the last grid point. </td>
<th style="vertical-align: top; text-align: left;">longitudeOfLastGridPointInDegrees*1000
</th>
</tr>
<tr>
<td> 9 </td>
<td> Latitude at which the Mercator projection cylinder
intersects the Earth(Latin). </td>
<th style="vertical-align: top; text-align: left;">latitudeAtWhichTheMercatorProjectionCylinderIntersectsTheEarthInDegrees*1000
</th>
</tr>
<tr>
<td> 10 </td>
<td> Reserved. Set to 0. </td>
<th style="vertical-align: top; text-align: left;"><br>
</th>
</tr>
<tr>
<td> 11 </td>
<td> Scanning mode flags (see <a
href="/publications/manuals/d/gribapi/fm92/grib1/show/ctables/">WMO
code table 8</a>) </td>
<th style="vertical-align: top; text-align: left;">
<p>iScansNegatively</p>
<p>jScansNegatively</p>
<p>jPointsAreConsecutive</p>
</th>
</tr>
<tr>
<td> 12 </td>
<td> Number of vertical coordinate parameters. </td>
<th style="vertical-align: top; text-align: left;">NV<br>
</th>
</tr>
<tr>
<td> 13 </td>
<td> i direction grid length. </td>
<th style="vertical-align: top; text-align: left;">longitudinalDirectionGridLength<br>
</th>
</tr>
<tr>
<td> 14 </td>
<td> j direction grid length. </td>
<th style="vertical-align: top; text-align: left;">latitudinalDirectionGridLength<br>
</th>
</tr>
<tr>
<td> 15-16 </td>
<td> Reserved. Set to 0. </td>
<th style="vertical-align: top; text-align: left;"><br>
</th>
</tr>
<tr>
<td> 17 </td>
<td> 0 Regular grid. </td>
<th style="vertical-align: top; text-align: left;"><a href="/publications/manuals/d/gribapi/keys/grids/">gridType</a>
</th>
</tr>
<tr>
<td> 18 </td>
<td>
<pre>Earth flag:<br> 0 Earth assumed spherical with radius 6367.47 km.<br> 64 Earth assumed oblate spheroidal with size as determined by IAU in 1965:<br> 6378.160km, 6356.775km, f=1/297.0<br></pre>
</td>
<th style="vertical-align: top; text-align: left;">earthIsOblate
</th>
</tr>
<tr>
<td> 19 </td>
<td>
<pre>Components flag:<br> 0 Resolved u and v components of vector quantities relative to easterly<br> and northerly directions.<br> 8 Resolved u and v components of vector quantities relative to the defined<br> grid in the direction of increasing x and y (or i and j) coordinates<br> respectively.<br></pre>
</td>
<th style="vertical-align: top; text-align: left;">uvRelativeToGrid
</th>
</tr>
<tr>
<td> 20-22 </td>
<td> Reserved. Set to 0. </td>
<th style="vertical-align: top; text-align: left;"><br>
</th>
</tr>
</tbody>
</table>
<p> Grid lengths are in units of metres, at the parallel
specified by Latin.
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