Gough Island by Tom ScSherry

Gough: The remote island that brings the weather close to home

Every October, a small crowd gathers at the East Pier Quay at Cape Town to welcome the SA Agulhas II home. On-board is a small group of people that just spent a year at one of the most remote places on Earth with a constant human presence. It’s called Gough Island.

The Subantarctic and Antarctic are extreme regions both in look and feel. Conditions are harsh, and landscapes daunting. Yet, we keep on sending people there, for the weather.

Gough-Island-by-Tom-McSherry
Gough Island (photo by Tom McSherry)

Where is Gough Island?

Gough is described as a lonely place. The total human population numbers five to eight people: three meteorologists, a doctor, a diesel mechanic and field assistants. Though most South Africans are unaware of the small team’s presence on Gough, their persistent work benefits us all, and reverberates far beyond the borders of the country.

Gough Island lies about 2 600 km from Cape Town, and just over 3 200 km from the point closest to us in South America. The island is part of the Tristan da Cunha group of islands, which lies about 400 km North West from Gough. The islands are, with Saint Helena, British territory.

Since the 1950s, South Africa has been leasing a patch of land to run a weather station, which is now technically a district of Cape Town. The weather station is managed by the South African Weather Service (SAWS). The members of the teams stationed there are part of the South African National Antarctic Programme (SANAP). As with all of the country’s Antarctic stations, it is administered by the Department of Environmental, Forestry and Fisheries, Directorate: Southern Ocean and Antarctic Support.

Inspecting-the-Stevenson-screen on Gough Island
Inspecting the Stevenson screen on Gough Island (photo taken 1978)

Gough Island is 91 km² big. Peaks rise to 900 m above sea level. There are also small satellite islands and rocks; places like Saddle Island, Round Island, Cone Island, Lot’s Wife, Church Rock, Penguin Island and The Admirals. Conditions are harsh. The island clings onto the edge of the “roaring forties” in reference to its location between 40° and 50° south in the South Atlantic, and the frequent gale-force winds. Summers are cool, rain falls often and sunshine is scarce.

This then, is where the South African team observes various climatic parameters and keeps an eye on the automatic weather station. Port Meteorological Officer for the SAWS (Cape Town Weather office), Mardené de Villiers, explains that they do this in 24 hours shifts, 365 days a year.

Gough Island and weather forecasts

The automatic weather station includes temperature and humidity sensors, a wind sensor and a pressure sensor, says Mardené. The observer on duty, one of the three meteorologists based on Gough also temperature, humidity, pressure, wind speed and direction, horizontal visibility, cloud height and type, present and past weather, and rainfall.

Twice a day they also launch a weather balloon into the upper atmosphere. Mardené explains that the balloon’s flight into the upper air provides a crucial vertical profile of the atmosphere. Here, the instruments collect real-time temperature, humidity, pressure and wind speed and direction.

Gough Islands birds
A young Wandering Albatross (Photo by Tom McSherry)

Last, she says, they also monitor data from a mounted weather buoy on Tristan da Cunha, where valuable atmospheric pressure data is collected.

The weather station thus operates much in the same way as others across South Africa, which also commonly provides hourly climate observations and upper-air ascents (the weather balloons). Yet, the volcanic island’s location makes the data from here particularly important.

Data from the west

The majority of the weather systems affecting South Africa originate to the west of the country, says SAWS Senior Forecaster, Kate Turner: “This is because the predominant wind flow that governs these weather systems is from west to east, which results in the weather systems affecting South Africa moving in the same direction.” As a result, it is crucial to have data stream to the west of South Africa to understand and gather information of the approaching weather, she explains.

Looking to what lies to the west of country, the choices of locations for weather stations are severely limited. In fact, the whole region is described as “extremely data sparse for climate studies”. Gough is one of the few locations filling this gap.

Kate says that the data from Gough is not only beneficial for information on approaching weather systems, but also for a better, 3D picture of the atmosphere. This data gets fed into numerical models to show us the state of the atmosphere.

“The more data points we have from across the southern African domain, including land and ocean, to “colour in” and map the current state of the atmosphere, the better the model forecast will be.” If you do not have good and sufficient data to feed into the models, she says, you cannot expect good, high quality forecasts.

As such, the data from Gough is really important for weather forecasts and for warnings of looming severe weather. Kate says that the data gathered from Gough and other stations over the decades is “extremely important” not only for research purposes, but also to understand climate conditions and to map climate change.

The impact of the data ripples across and beyond South Africa.

Why we should care about this data

First, it is used for direct day-to-day forecasting for the island itself and particular operations that require an indication of the weather, says Mardené .

Then, the data from here is vital to forecast weather across southern Africa. “The data is also sent to the Global Telecommunication System (GTS) where various international users access it to be incorporated into global weather models.” Last, it is also used for various research projects.

Now reaching back over half a century, the data set from Gough has become indispensable to local and international climate studies. We access the fruits of their labour easily. We can see it every time we check the weather forecast online, open the newspaper or watch it over the news.

Gough Island weather readings
As was required by the Weather Service the weather balloon is released on Gough Island twice a day (photo taken in 1968)

Still, the effort that goes into the data is more obscure. Digging into the archives of the Antarctic Legacy of South Africa, our history in the region is marked by great achievement, as well as tales of “mutiny, attempted murder, shipwreck, drownings and much more.” That’s how it was described by Lieut. Frank McCall, who led the first missions to build South Africa’s weather stations in the region.

A tale of great adventure

South African activities in the Antarctic already began in the previous century, when sealers launched their ships there from Cape Town. The national flag of the Union of South Africa was formally raised on Marion Island for the first time on 29 December 1947. The feat was part of operation Snoektown, a naval operation during which the uninhabited, Subantarctic archipelago of the Prince Edward Islands was officially annexed by South Africa.

According to Lieut. McCall, “The story begins in 1954 when Jannie Smuts, the Prime Minster of South Africa, sent a confidential message to certain scientific authorities warning that South Africa had better occupy the Prince Edward Islands before Russia did. This would be by means of a weather-research station.”

Volunteering for the job, McCall wrote of “a lonely, wild, volcanic island halfway to the Antarctica mainland,” where they subsequently put a small group of weathermen in a tiny hut. “They were the only human inhabitants,” he wrote. “This was Marion Island.” At least one relief expedition per year to the weather station on Marion has been carried out ever since.

Motivation for the establishment of the next weather station, on Gough, was driven by the International Geophysical Year of 1957/58. The initiative entailed scientists from around the world taking part in a series of coordinated observations of various geophysical phenomena.

Activities spanned the globe from the North to the South Poles, but special attention was given to the Antarctic. Here, research on ice depths yielded radically new estimates of the Earth’s total ice content. The research also contributed to improved meteorological prediction, advances in the theoretical analysis of glaciers, and better understanding of seismological phenomena in the Southern Hemisphere.

Team members of Gough 8 preparing the catch of the day for a meal.

The weather stations that followed

In preparation, the weather station was established on Gough in 1956, to be operated by South Africa. McCall writes of a mission to “work out where to put a base on that uninhabited island which lies south of Tristan Da Cunha.” Pending the building of the base, he writes, some weathermen were left there in a small hut. McCall writes that on his return six months later, the leader was “raving”. “He had tried to exercise authoritarian rule over his group and they “sent him to Coventry” (refused to talk to him.)”

A weather station was consequently built at a place called ‘The Glen’, and later moved to the South Western lowlands of the islands (in 1963) for more accurate weather observations.

South Africa has paid expensively for its presence on Gough. According to a History of South African involvement in Antarctica and at the Prince Edward Islands by J Cooper and RK Headland, “Gough Island may be reckoned as a dangerous place: four team members have died there since 1956, three by exposure in the mountains and one by drowning while fishing.”

SANAP’s last scientific station was built on the Antarctica mainland in 1961. First called Norway station, it was later renamed South African National Antarctic Expedition (SANAE) and has been in continuous operation since. The current South African research base, SANAE IV is located at Vesleskarvet, Queen Maud Land.

Though it cannot be described as a hospitable environment to humans, Gough Island is special for various reasons beyond meteorology. It’s a UNESCO Natural World Heritage Site, a Ramsar Wetland of International Importance and part of the Tristan da Cunha Nature Reserve. It’s also been declared an Important Bird and Biodiversity Area, and is considered home to one of the most important seabird colonies in the world.

Gough’s other inhabitants

Gough Island is one of the only homes to the critically endangered Tristan Albatross. January dated newsletters written by those stationed there, tell of the interior of the island dotted with white birds nested on mounds that hold their enormous white eggs. While the Tristan Albatross is perhaps its most famous avian inhabitant, the island is also home to almost the entire global breeding populations of the endangered Atlantic Petrel and MacGillivray’s Prion.

Tristan albatross on Gough Island
A Tristan Albatross (Gough Island)

These are some of the 22 breeding seabird species found on Gough Island. It’s also home to 35% of the population of the endangered Sooty Albatross, and about 20% of the endangered Atlantic Yellow-nosed Albatross. The Gough Finch and Gough Moorhen are endemic to the island.

Unfortunately, the birds are paying a price for people arriving at the island. Docking at Gough in the 19th century, house mice reportedly arrived with those sealers. They are famously big, having grown substantial larger than house mice elsewhere due to the favourable conditions the island offers. There are no natural predators or competition for the food that’s available in ample supply.

Especially in winter, this takes the form of vulnerable Tristan Albatross and Atlantic Petrel chicks. Bird numbers have dropped dramatically as a result. In partnership with the Royal Society for the Protection of Birds, the Department of Environmental, Forestry and Fisheries is launching a mice eradication programme in 2020.

Do you want to go to Gough?

The island is not completely out of bounds to South Africans. As per agreement, the annual Gough Island relief voyage with the SA Agulhas II also takes paid passengers to Tristan die Cunha on its outward and return voyage, stopping at Gough along the way. For most of us however, the near imperceptible connection to Gough remains to be via our everyday weather forecasts.

Notes

  • Thanks to the Antarctic Legacy of South Africa (ALSA) for the photographs used in this article.
  • The featured image was taken by Tom McSherry
  • This article was first published by the Water Research Commission, in the Nov/Dec 2019 edition of the Water Wheel

Sources

  • History of South African involvement in Antarctica and at the Prince Edward Islands by J Cooper and RK Headland (S. Afr. Antarct. Res., Vol 21 No 2, 1991)
  • Where is Antarctica, by Lieut. Frank McCall, 1955 (general report on his visits to Antarctica and Sub-Antarctic islands.)
  • https://www.environment.gov.za/projectsprogrammes/ antarctica_southernoceans_islands
  • The Antarctic Legacy of South Africa archives (http://blogs. sun.ac.za/antarcticlegacy/)
  • The impacts of introduced House Mice on the breeding success of nesting seabirds on Gough Island by Anthony Caravaggi, Richard J. Cuthbert, Peter G. Ryan, John Cooper and Alexander L Bond, published in the Ibis International Journal of Avian Science: , 22 October 2018
  • http://www.nas.edu/history/igy/

Leave a Reply

Your email address will not be published. Required fields are marked *