Altimeters monitor wave heights around the British Isles.
21, October 2020
Big waves are fun — for surfers. For seafarers, coastal equipment designers and inhabitants, they are potential dangers that have to be taken into consideration. Altimetry cannot give the wave heights every hour — at least not without many many more satellites — but it is a good technique for identifying trends and gives us some idea of the minimum and maximum heights.
The North Atlantic may not be the roughest part of the ocean (that's the Southern Ocean), but it does have the most marked variations, and its coasts are quite populated. The British Isles, along with Brittany, bear the brunt of ocean storms, so potential damage has to be assessed.
The top image below shows the mean wave heights derived from altimetry off the British Isles for the years 1993–97, in winter (December–February), spring (March–May), summer (June–August) and fall (September–October). The seasons are very well marked to the west of the Isles, with rough winters, identified by wave heights that can reach 14 meters and even as high as 20 meters, and calm summers.
The bottom image shows the maximum wave heights measured by altimetry in 1994.
Mean wave heights for the years 1993–97
Mean wave heights from altimetry for the years 1993–97
(source: Southampton Oceanography Centre)
Maximum Significant Wave Heights (SWH) in 1994
Maximum wave heights measured by altimetry in 1994
Full Resolution Source: Southampton Oceanography Centre
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