Tidings from Marion Island
You may have wondered why next years data (2013) has only been available since early June. It has been customary for me to publish the following years information around March. This is due to the fact that I have spent the last 13 months on Marion Island in the capacity of the resident Geo/Space Science Engineer. We have very recently returned on what was the final voyage of the SA Agulhas to Marion. Five days of the calmest weather I have ever experienced in the southern ocean - waters which are notorious for producing swell from hell.
The tidal range around the sub-antarctic Marion Island (47 degrees south) is as expected significantly less than around the South African coast. It is approximately 1 metre whereas Durban is in the order of 2.3 metres. The occurrence of a spring tide on Marion is 2 and a half hours after Durban measured on the same time zone. The rolling deep sea swell on the other hand is frequently classic and pounds away at the steep cliffs. There is a online tide-gauge which forms part of an international network on sea level monitoring and can be observed at this link: Sea Level Monitoring
Of-course, if you live in the intertidal zone, the tide will determine your existence even if it is only 1 metre. The most obvious and visible life form in that zone is the astoundingly tough Bull Kelp. The apt opinion of celebrity Betty White as to what constitutes "tough" could certainly apply here. Perhaps one should just refer to it as Cow Kelp and be done with it.
Other forms of life would certainly appreciate a little extra water - even if it is just 1 metre. The female elephant seal peeking through the kelp is in close attendance by two Killer Whales. She would have appreciated an extra metre of water a great deal in order to escape onto the rocks. (Thank you Ryan Reisinger for the great images)
Bar for two months in the early part of the year, Killer Whales can be spotted virtually daily.
More underwater visuals on Killer Whales can be seen at this YouTube link:
Killer Whales and Hula Hoops