From a submariners point of view, a Keel is a downward projecting ridge on the underside of the ice canopy - the counterpart of a Ridge. A Bummock is the counterpart of a hummock on the underside of the ice canopy.
Definition Source :
Similarity to Source :
Recommended Attributes :
Distinguishing Features :
Note that there is no established WMO symbol to depict “Keel/Bummock”. It is recommended that the WMO symbol for Ridges/Hummocks be inverted, so the straight line representing the water surface is at the top - and used for Keels/Bummocks. This discrepancy can be corrected in a future revised edition of the referenced WMO documents.
On behalf of the IHO Member States, the International Hydrographic Bureau would like to thank Korea Hydrographic and
Oceanographic Agency(KHOA) of the Republic of Korea for giving active support in the development of the S-100 GI Registry