At Macquarie Island, a walking track is given an update and BOM meteorologist Barry Becker provides details on the first winter blast.

Track work with Chris

I’ve been out and about a fair bit in recent times undertaking repairs to some of the walking tracks on the island. Whenever possible, walking around the sensitive landscape of Macca is confined to the walking tracks. Walking tracks are usually confined to harder rocky terrain, but often tracks will cross more sensitive areas.

Occasionally, repairs are required to be undertaken in order to repair damage or limit further damage occurring. Over the last year or two, stockpiles of timber decking have been flown into different locations by helicopter during the island’s summer resupply. The sites selected have been identified by previous rangers as being sensitive and prone to damage by foot traffic. Progressively, the works program has migrated to each of these locations and narrow sections of the double plank walkway have been constructed. 

Completing some of these remediation works before the onset of winter will ensure that nature’s regenerative power will kick in as the weather warms up in the coming spring. The vegetation on Macca is really starting to show signs of regeneration with the removal of rabbits. 

People are always looking for a chance to get off station or vary their tasks a little for the day and I’m always glad of a helping hand and a bit of company. Aaron wrote a story about helping out just recently titled 'ranger step aerobics’. 

Working on the Island Lake track, FTO Marty dropped in for a few hours and lent a hand with the laying of timber decking. Karen and Nick from the MIPEP team also dropped by to help for the day — a welcome change to their routine after scouring the landscape for any sign of rabbits. Nick particularly enjoyed swinging the sledge, relishing the chance to do a proper bit of physical work. The hunting dogs took the moment to have a well earned break.

Chris, standing almost knee deep in mud and next to some unfinished boardwalk, pausing for a moment to work out the best way to get the job done
The tall and the short of it. Nick and Chris hard at it constructing a new section of track over some bog. Chris is knee deep in mud while Nick stands by with a sledge hammer in one hand ready to get a sweat up
View of the new boardwalk track on the Island Lake Track near Scoble Lake. Nick can be seen some way down the track helping to fix wire netting to the boards for more traction
Finn, the MIPEP hunting dog (white labrador) is taking a well earned break in the foreground. In the background Chris, knee deep in mud is holding a post while Nick is just about to strike the top of the post with a sledge hammer
Finn, the MIPEP hunting dog (white labrador) lifting his head to see if it’s time to go back to work yet. Nick can be seen in the background carrying some timber on his shoulder for the new board walk track
The new finished board walk track. protecting sensitive vegetation. 130 metres of track was laid.

First winter blast

On Saturday night into Sunday morning we had our first big snowfall for this season.

It came about as low pressure system that passed over the island on Saturday and as it moved east it was followed by a colder southwest to southeast flow on Saturday night and through Sunday. This can be seen on the first three mean sea level pressure analysis charts shown below. Note that winds or flow is clockwise around a low and anticlockwise around a high.

We woke on Sunday to find snow had settled at the station and the slopes. Marty, Patty and Steve left station early Sunday for field training. Aaron and I took the opportunity of walking the loop track. It was stunning to see the countryside covered in snow. 

On Sunday night into Monday morning, the southwest to southerly flow over the island brought colder air from the deep southern waters near the Antarctic continent, shown on the next three charts. The result was frequent snow showers and blowing snow throughout Monday, with the temperature hovering between −4°C and −2°C all day, only managing to peak at a maximum of −1.4°C. This was not far off the coldest May day of −1.7°C.

Spare a thought for the wildlife as the ground temperature hovered around −5°C with the minimum ground temp of −7.1°C recorded.

The ‘cold pool’ of air moved northeast in the strong southwest flow and hit New Zealand with a cold, snowy blast on Tuesday, with heavy snow and cold temperatures recorded all over, including much of the north island.

By Tuesday morning the Macca weather returned to normal: a balmy 5°C.

Barend (Barry) Becker 

Weather map (MSLP) for 10am Saturday shows a low pressure system over Macquarie Island
Weather map shows that 12 hours later the low is now to the east and the flow over Macca has turned colder SW to S
Weather map for 10am Sunday shows the low is now south of NZ and the flow over Macquarie Island is generally southwesterly
View from Hasselborough House porch last Sunday morning, showing the ground, building roofs and distant hills covered in layer of snow
A close up of a young elephant seal, lying on the snow, with what appears to be a smile on its face
A view looking south along the track with tussock alongside and the distant hills slope towards the east coast. There is a thin layer of snow cover
View of a snow covered slope in the foreground, with Aaron at the lower part of the slope taking a picture of a king penguin above him up the slope. The station and North Head can be seen in the background
On the left of picture is Aaron standing on the snow covered slope at the base of Gadgets Gully. There are a few penguins on the left slope of the gully
Looking down Gadgets Gully. The slopes of the gully are covered in snow and you can make out the snow covered beach at the bottom of the gully with the turquoise coloured sea beyond
View from the Gadgets Gully track across the snow covered landscape. A small creek in a broad valley runs to the edge of Gadgets Gully. The ocean can be seen beyond the landscape with North Head in the top left of picture
View of the snow covered Doctors Track with Aaron on the track just ahead. North Head and the Southern Ocean can be seen beyond the slopes
Weather map of 10pm Sunday, showing the flow near Macquarie Island has turned SSW bring colder air from Antarctic waters
Weather map from 10am Monday shows that 12 hours later Macca is still in the cold southwesterly blast
Weather map for 10pm Monday, shows that the cold flow has lost its push as a weak ridge of high pressure approaches Macca from the west. It also shows that the cold southwest blast has passed over New Zealand
View of the station in bleak cloudy conditions. Snow is falling and the ground is covered in snow and ice
The snow covered Meteorological station enclosure on Macquarie Island with the white ‘Stevenson screen’ in the right foreground. this houses thermometers and other measuring instruments
View towards North Head and the sun, low in the sky beaming rays through the top and bottom of the cloud. In the foreground iare windswept tussock mounds with icy snow covered ground in-between
View south along the coastal tussock of West Beach, with some gentoo penguins and elephant seals amongst the tussock and the steep slopes in the background
Looking north along the coastal tussock of West Beach. Patches of snow throughout with a couple of young elephant seals amongst the tussock
View of West Beach covered with patches of snow. There are several elephant seals on the beach with a pair play fighting in the foreground. The setting sun is sending beams through the cloud
At sunset looking southwest across snow covered ground towards the distant slopes. There are tussock mounds across the landscape
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