iceberg

Iceberg A68-A curves around South Georgia

2-29 December 2020 15:00 UTC and 28 January 2021 15:00 UTC

iceberg
iceberg

The breakup of Iceberg A68-A, in December 2020, was observed in Meteosat and GOES imagery.

Last Updated

06 May 2022

Published on

02 February 2021

By Jochen Kerkmann (EUMETSAT) and Scott Bachmeier (CIMSS)

Iceberg A68-A, the planet's largest iceberg made headlines in July 2017 when the huge block of ice broke from the Larsen C Ice Shelf on the Antarctic Peninsula (see the case study Massive iceberg breaks off from Antarctica). In November 2020, the iceberg was back in the spotlight, as it is drifted toward South Georgia, a remote island in the southern Atlantic Ocean (see track of the iceberg (Credit: NASA Earth Observatory). The question was whether the large iceberg would get stuck (grounded) on the island’s submarine shelf, or if it would flow around the island.

The iceberg and South Georgia island are both visible in the GOES-16 Cloud Type RGB from 2 December (Figure 1). At that time the iceberg measured 135km long and 68km wide (see image with range overlaid) - comparable to the island’s length and width of 167km and 37km. On the image green colour denotes snow or ice (snow covered South Georgia, iceberg A68-A), red is thin, high-level cirrus clouds and the blue-cyan colour is low level water clouds.

GOES-16 Cloud Type RGB
Figure 1: GOES-16 Cloud Type RGB (RGB NIR1.3-VIS0.6-NIR1.6), 2 December 15:00 UTC (Credit: EUMeTrain ePort).

The iceberg was also visible on Meteosat-11 images, though at a very high viewing angle, i.e. at low spatial resolution. Figure 2 shows a comparison of the GOES-16 Natural Color RGB product (snow and ice in cyan colour) with the same RGB product from Meteosat-11. The difference in resolution/viewing angle is striking/outstanding.

GOES-16 and Meteosat-11 Natural Colour RGB comparison

Meteosat-11 Natural Colour RGB compare1
compare2
 

Figure 2: Comparison of GOES-16 and Meteosat-11 Natural Colour RGBs, 2 December 15:00 UTC (Credit: EUMeTrain ePort)