No Comments

Written by Dr Helen Bostock  (Marine Geologist, NIWA).

Date: 22/2/2013
Location: 64.838758°S, 142.310661°E
Weather: 20 knots, cloudy
Sea state: 2-3 m swell

Humpback whales

We are now half way through the voyage…. it seems to be going by quickly. While most people were at lunch today, we were visited by 5 or 6 large humpback whales (12-16 m in length): very appropriate for hump day!

The whales ended up swimming and playing around the ship for a couple of hours, putting on a spectacular display for us – breaching, flipper slapping and diving. Several of our photographers got some fantastic images and videos. We will provide these to the whale experts to help them identify the individuals; the experts have named many individuals from their distinct scars and black and white markings on the underside of their tails (also called flukes), and over many years have built up a database of pictures with which they compare whale sightings.

Humpback fluke. [Sue Reynolds]

Humpback breaching. [Sue Reynolds]

Humpback snout. [Sue Reynolds]

 

Aurora australis

Clear skies over several nights this week have treated those of us on the night shift to views of the aurora australis, or southern lights.

The aurora occurs within 10° to 20° of the magnetic pole (see blog post 16: The South Pole), although during geomagnetic storms it expands into lower latitudes. It is caused by the collision of particles and atoms high up in the atmosphere: the particles originate in the magnetosphere and the solar wind and are then deflected by the Earth’s magnetic field into the atmosphere.

Interestingly, NIWA’s atmospheric research station in Lauder, Central Otago, was originally established in the early 1960s to study the aurora australis.

Aurora australis. [Mark Fenwick]