Meteorology and its Application to Heard Island

Cloud vortices off Heard Island. Image credit: NASA GSFC (Terra/MODIS, 9/19/2011 for you satellite imagery junkies).

Meteorology is an important consideration for any outing, be it a trip to the grocery store or an extended expedition. You will prepare differently if the temperature is hot enough to melt butter in the shade than you would if it’s cold enough to flash-freeze a pot of boiling water.

There are two different things we will need to keep in mind for these preparations: climate and weather. Although they are related, they are fundamentally different. Climate is long-term, whereas weather is short-term. For instance, the average high temperature* for Minneapolis for January 4th is 24 F. That’s the climatological average; if you’re planning a trip to Minneapolis for January 4, 2016, that’s a ballpark of what to expect. Weather is more variable, of course. In 2015, the high temperature on January 4th was 12 F; in 2014, it was 35 F. That’s weather. Here’s an analogy: take two six-sided dice. On average, when you roll them, their sum will be seven (that’s the climate). However, you shouldn’t be surprised with a roll of three!

Last month at the Five Thirty Eight blog, Nate Silver did a great job analyzing the amount of weather at various cities across the US, and in general exploring this distinction and the limits of its usefulness. Unfortunately, his title is a bit misleading:

“Which City Has The Most Unpredictable Weather?”

His use of unpredictable has nothing to do with the skills or abilities of the local meteorologists.** Instead, it is a reflection of the variability away from the climate average. That is, if you use the climate average as a forecast, how likely is it to be correct? In some areas, such as Phoenix, AZ, the climate average high temperature is a very good predictor. In others, like Minneapolis, the departures from average can be larger and more frequent, as exemplified above.

So, now that we have that discussion out of the way, and deferring things like uncertainty to another post, what do we know about Heard Island?

Expect cool temperatures, wet weather, and plenty of wind. The vast icy waters surrounding the island keep conditions from changing much. Temperatures remain near freezing year-round, with monthly average temperatures in summer still only 5.2 C (~41 F). The ocean provides plenty of moisture too; a research expedition from 1948-1954 recorded precipitation on 75% of days at Atlas Cove, one of the more accessible parts of the island.

The volcano can make its own weather by disrupting the west-to-east winds. Windward locations tend to see more fog and rain (like the coastal parts of San Francisco), while leeward areas see more sun and warmer temperatures (like Berkeley or Palo Alto). Lenticular clouds, formed when the humid air is pushed up around the mountain, are also found at Heard Island. Other conditions can cause cloud vortices when the smooth flow of wind is disrupted while passing the island, as seen in the picture at the top of this post.

In the southern hemisphere, there is much less land to disrupt the smooth flow of air than there is in the northern hemisphere. Consequently, the winds tend to be stronger more consistent. At Atlas Cove, the average wind speeds are around 26-33.5 km/h (16-21 mph), with gusts recorded up to ~180 km/h (110 mph). That means we can expect damage similar to that found from a borderline EF1/EF2 tornado.***

In short, the climate of Heard Island is near-freezing, wet, and strongly influenced and moderated by the water around it. Be prepared for cold, snow, rain, and wind. There will be some sunshine in there too, but it won’t be the norm.

* The National Weather Service computes this over the 30-year period of 1981-2010.
** Variable would have been a more appropriate word, because devious has deviated from the sense which would be useful here.
*** Tornado categories use the Enhanced Fujita scale (0-5, 5 is strongest), and are estimates of wind speed based on damage. Obviously we’d rather use a direct measurement and have our camp sturdy enough to not have damage to use for estimating wind speed. More on the inner workings of the (enhanced) Fujita scale can be found at the NOAA Storm Prediction Center.

Global Warming, and Stephenson Glacier Retreat

Annual global surface temperature difference from the 20th century average.  2014 is the 38th straight year above average.  Image credit: NOAA.
Annual global surface temperature difference from the 20th century average. 2014 is the 38th straight year above average. Image credit: @NOAA.

Two things came to my attention today which are of particular interest.

First, NOAA has announced that globally, 2014 was the warmest year on record, and the 38th straight year of above-average temperatures. Continued action will be needed in 2015 to reverse this trend. Every delay makes fixing the situation more difficult.

Second, Mauri Pelto has written today about the retreat of Stephenson Glacier and the formation of a lagoon on Heard Island. In 1947-1948, when members of the Australian National Antarctic Research Expedition (ANARE) spent 15 months at Heard Island, they found Spit Point, on the southeast side of the island, was only accessible after crossing Stephenson Glacier. Imagery from LANDSAT shows substantial retreat, as do photographs from a 2004 expedition to Heard Island.

Landsat 2010 image, annotated by Mauri Pelto.  Arrows mark the toe of the glacier in 2001 (purple), 2010 (red), and 2013 (yellow).  Additional images are available on Mauri Pelto's blog.
Landsat 2010 image, annotated by Mauri Pelto. Arrows mark the toe of the glacier in 2001 (purple), 2010 (red), and 2013 (yellow). Additional images are available on Mauri Pelto’s blog.

Today, where once Stephenson Glacier met the ocean, there is now Stephenson Lagoon. The toe of the glacier has retreated inland, and to my eye appears to have moved about 4 km. With a warming at Atlas Cove of 1 °C over 1947-2001, the retreat is not surprising.

On an Island Far Away…

World map.  Image credit: NASA
World map. Image credit: NASA. Click for full size.

In order to better understand the project, and what I will be doing on Heard Island, it is important to know things about the island itself. Perhaps the easiest thing to talk about is where the island is.

Here’s the same world map as above, but now with additional annotation. Shown in partial transparency is the western hemisphere antipodes (opposite side of the world). A red arrow points to Heard Island, and a red circle in Saskatchewan marks Heard Island’s (approximate) antipode.

Red arrow marks location of Heard Island; red circle marks approximate location of Heard Island antipode.
Click for full size. Red arrow marks location of Heard Island; red circle marks approximate location of Heard Island antipode. Adapted from NASA.

As you can see, Heard Island (technically Heard Island and McDonald Islands) is far away from other land, and about as far from Minnesota as one can go without being in space.* There are no airports on the island. Only by sea (or helicopter for the final mile) can we reach the island. For our expedition, there will be no helicopter.

To reach the island, our team will board the Akademik Shokalskiy in Fremantle, Australia (southwest corner, near Perth) RV Braveheart in Cape Town, South Africa. We will then sail southwest southeast through the Roaring Forties and into the Furious Fifties, and about ten days after departure (weather permitting, and in that part of the world it is often inclement) we will arrive.

Heard Island is of a modest size, 20-30 km across (13-20 miles). In the center is a 9000-foot tall volcano, Big Ben, which I will elaborate on in a further post. Mantling Big Ben and flowing down to the sea are glaciers, which cover the majority of the island. In many places, the ice forms sheer cliffs where it enters the sea, making landing on the island difficult.

There is no permanent human settlement on Heard Island. An early research party stayed for fifteen months during 1947-1948 [2], and the most recent winter expedition was in 1992. It is an Australian territory, and home to one of Australia’s two active volcanoes—the other being the smaller, nearby McDonald Island.

Because Heard Island is so remote and has such active surface geology (volcano, glaciers, streams, high wind) and has no permanent inhabitants or introduced species, it has been designated a UNESCO World Heritage Site.[2]** These conditions make the island an excellent natural laboratory to study all sorts of phenomena from climate change to glaciology to biology.*** I’ll have lots more on all that coming up in future posts!

[1] Arthur Scholes, Fourteen Men, E. P. Dutton, 1952.
[2] http://whc.unesco.org/en/list/577 UNESCO organization. Retrieved January 8, 2015.

* Space is much closer to Minneapolis than Heard Island, or even South Dakota.
** For more on this general topic, the Wikipedia page on the Geography of Heard Island and McDonald Islands is informative.
*** While it is unlike me to paraphrase J. D. Salinger’s Holden Caulfield (from Catcher in the Rye), if you thought it was a somewhat tricky question figuring out where ducks go in the winter, think about where these penguins go in the winter. They do migrate away from Heard Island.[1]

Update 5/14/2015: Vessel and port of departure have changed. More info here (my blog) and here (official).

Welcome!

Welcome to The Inquisitive Rockhopper!

Named after rockhopper penguins, which are naturally inquisitive, the title plays on the author’s affinity to hop about on rocky outcrops admiring the geology.

This draw to neat rocks has extended so far that I am going on the Heard Island Expedition to (you guessed it!) Heard Island in November and December of 2015 March and April, 2016. While there I will do some science—perhaps assisting with a population survey of rockhopper penguins and other birds—as well as lots of ham radio as VK0EK.

On this blog I intend to cover a review of the scientific knowledge so far acquired on or about Heard Island, what I hope to accomplish while I’m there, and what some of the challenges are associated with this expedition. I am also on Twitter as @i_rockhopper.

Update 5/13/2015: Expedition has been rescheduled for March/April, 2016. More info here (my blog) and here (official).

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