Daily Archives: May 26, 2014

Life

A Coast to Coast odyssey – where it all started

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It must be around 2 years ago now that a group of four friends and I first spoke about completing the Coast to Coast (C2C) walk across northern England.  And so here we all are, eager to get going on our C2C odyssey on 26 May, 2014!

The walk starts at the small village of St Bees on the Cumbrian coast and ends at Robin Hoods Bay on the North Sea coast.  It was devised in 1971/72 by noted English fell-walker, Alfred Wainwright and the details of the walk were published in his 1973 book – A Coast to Coast Walk (a revised edition is still in print!). Since then the C2C has achieved international popularity and around 10,000 people from all parts of the world now complete it each year.  For example, we came across a chap from the USA down in the village this-morning.  He told us that he and his 78 year-old mother are starting the walk tomorrow!  We may well see them on the track. A recent survey of long-distance walkers rated the C2C as the second-best long-distance walk in the world!

But it isn’t without it’s challenges.  It is just over 300 km long (varies with the precise route taken – there are several alternatives in a number of places, frequently a high altitude option (with expansive, spectacular views) and a low altitude, more intimate parallel option).  As well, there are plenty of hills and mountains to climb, with the total ascent required over the walk around 7,000 m.  And maybe even more important, the amount of descent is the same (assuming sea-level is the same in the Irish and North seas!).

So with these challenges in mind, we decided to complete a series of one and two-day training walks around South-east Queensland (Australia – where we all live), starting about 12 months ago.  Over this period we have walked close to 200 km as a group, mostly along the excellent National Park network of walks.  These walks culminated in a 45 km 2-day trek along the ‘Border Track’ from O’Reilly’s to Binna Burra and return. Here we are at Binna Burra  about to set out on the return journey on the second day of our walk. IMG_4615a And so on Saturday, 24th May, we all converged on Manchester Airport from various parts of the world (Rome, Paris, London), meeting at the Delice de France Café, Terminal 3.  Here we are, all looking excited in anticipation of what is to come! IMG_0159 The couple on the left are Doug and Tricia Smith, while the couple on the right are Laurie and Tricia Sheahan – both have been close family friends for nearly 40 years!  While we have had many very enjoyable experiences together, this is the first time we have engaged in an activity as enterprising as this.  But I must say that our preparatory walks together have been most enjoyable.  My wife, Nola, is a great Anglophile and I’m sure would have enjoyed many things about this trip.  But  she is not a keen long distance walker  ….. so stayed at home this time.

From Manchester, we travelled by train to Barrow-in-Furness and then up the very picturesque Cumbrian coast to St Bees.

We then spent Sunday 25th May relaxing in St Bees, readying ourselves to start our great adventure.  Opposite the Fairladies Barn, our B&B accommodation in the main street of St Bees, is the little pub …. see below.  Here, we have had lashings of home-cooked fare on the last two evenings, along with a pint or two.  Roast beef and Yorkshire Pudding, meat pies (with plenty of meat), and blackberry, apple and rhubarb pie have variously kept us (too well) fed and ready to go. IMG_0245 The C2C from west to east starts on the beach at St Bees and proceeds immediately up onto the high cliffs of the St Bees Headland.  If you were sitting in the tea-house in the building on the left in the picture below, you would see us disappearing into the distance along this high cliff-top 0n the start of our journey.  After several hours we will turn inland towards the Lake District and ultimately, the North Sea coast.  We intend to travel at a leisurely pace compared with many who complete this walk.  Our plan is to spend 20 days walking (averaging 15 km/day) and have three rest days along the way.  IMG_0231We found to our surprise that the tea-house listed a slice called ‘Australian Crunch’ among its delicacies.  It must be popular since it was sold out.  So I can’t tell you what it was like.  But the ‘Bakewell Slice’ was delicious!

My plan is to make regular posts along the way.  But I can’t promise any particular frequency since it will all depend on many factors, including internet access (or lack of it) in some of the small villages.  And there may be other activities that compete for my time along the way as well!

Climate Science

Antarctic images

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In this post I’ve included a series of explanatory images of the Antarctic in order to assist understanding the peril we are in from changes there, and why the Antarctic is going to be central to the climate change story over the coming centuries. What happens to the grandchildren of those who are children now is the big concern. In large part these images relate to items 2-4 of Climate clippings 96.

The first shows the giant vortex of winds, the strongest for at least 1000 years, ripping around Antarctica in a tight circle:

Figure 1
Figure 1

These winds draw rain away from southern Australia, and isolate Antarctica to some extent in terms of atmospheric warming. But they also churn up the ocean, leading to deeper mixing of heat and greenhouse gases.

Both the deep and the shallow formations of the thermohaline circulation system wrap themselves around the Antarctic:

Figure 2
Figure 2

One way or another warm water is penetrating through to Antarctica. The underlying topography of Antarctica reveals much of the land lying below sea level:

Figure 3
Figure 3

The borderline between blue and green marks sea level. Warmer water is coming directly into contact with the ice sheet and chewing away at the bottom of the ice shelves which form plugs holding up vast quantities of ice in the glaciers stretching hundreds of kilometres inland. The following image shows how the continent drains:

Figure 4
Figure 4

There is concern now that West Antarctica has tipped and with East Antarctica also more vulnerable than previously thought, sea level rise of some metres is now inevitable even if we were to somehow instantly curb greenhouse emissions.

Greenland is quite a different problem. For starters the underlying topography is saucer shaped, with glaciers exiting to the sea through ‘gates’. This image shows the topography:

Figure 5
Figure 5

Greenland melts very much from the surface, so its largely a matter of meltwater penetrating, indeed plunging at times, through the surface to the rock below and glaciers speeding up. This image shows some people standing where I’d never stand:

Figure 6
Figure 6

This image shows melting covering the entire Greenland ice sheet for a few days in 2012:

Figure 7
Figure 7

The panel on the left shows a more typical summer melt pattern, which is advancing noticeably over short time frames of a few years.

In the Antarctic, this image shows surface warming over the period 1981-2007:

Figure 8
Figure 8

But with the average temperature around -39°C on the East Antarctic ice sheet, which is four kilometres high, that huge lump of ice is relatively stable. This image from NASA in 2005 shows significant perimeter surface melting around East Antarctica:

Figure 9
Figure 9

The new research sees concern that warmer sea waters may destabilise the ice further inland than previously thought. Match the red blobs on East Antarctica with the drainage map at Figure 4.

Of some some concern and some comfort is the Andrill Project which found that “the West Antarctic ice sheet has collapsed and regrown over 60 times in the past few million years”. This image shows what happened about a million years ago over a 12,000 year period:

Figure 10
Figure 10

Concern because the Andrill research shows what can happen with mild orbital forcing (the Milankovitch cycles) as the main driver. I understand that CO2 concentration back then was only 400 to 450 ppm, which is where we now, implying that we are already committed to wasting the West Antarctica ice sheet. There is some comfort, however, that a change in the orbital forcing, which is far weaker than what we are doing now, arrested the melt in West Antarctica and brought the ice sheet back again. There was no tipping point which saw the whole East Antarctic sheet disappear.

For perspective I’ll post one of my favourites, a graph from David Archer in 2006 showing the broad relationship between temperature and sea level:

Figure 11
Figure 11

Do not connect the dots with straight lines. Most importantly, I think we now stand at the upper level of a 2°C interval where the sea level did not change much. The NH continental ice sheets had disappeared and the remaining ones – Antarctica, Greenland and the Arctic – were not seriously in play. Even now the main sources of sea level rise lie elsewhere. This table (13.1 from the IPCC5 WG1 Technical Summary) shows what’s happening:

Figure 12
Figure 12

That’s hard to read, so here are the figures for the average annual expansion for 1993-2010:

    Thermal expansion – 1.1mm

    Glaciers except Greenland and Antarctica – 0.76mm

    Glaciers in Greenland – 0.10mm

    Greenland ice sheet – 0.33mm

    Antarctic ice sheet – 0.27mm

With 4-5°C we can expect complete deglaciation and 75 to 80m sea level rise, made up of East Antarctica 59m, Greenland 6-7m, West Antarctica 5-6m, other glaciers and ice caps about 0.5m and thermal expansion, I don’t know, but I think in single figures. Greenland and Antarctica are accelerating rapidly and some time this century will become the top two contributors. These graphs from Skeptical Science are instructive:

Figure 13
Figure 13

Greenland and West Antarctica are in a death spiral of accelerating ice sheet decay. It’s happened 60 or more time before in recent paleo history. West Antarctica, being more vulnerable may overtake Greenland.

One could say from this that East Antarctica is not yet in play, but science seems to suggest it is not far away.

When ice sheet decay gets going Hansen sees it as possibly progressing in geometric fashion, producing a curve like this:

Figure 14
Figure 14

My thinking is that East Antarctica will tip sometime in the next decade, and that ice sheets will decay from there in a pattern that is more exponential than linear. Hansen’s scenario, which he puts forward as a serious possibility, does not look crazy.

I suspect that we are already committed to double digit sea level rise, and there’s not a thing we can do to prevent it; the question is when will it happen? We can only adapt and minimise.

I suspect also that things will go seriously pear-shaped during the latter part of this century. Pity our grandchildren’s grandchildren.

Update: There is a short ABC video news item about the Antarctic ice melt doubling since the last survey. At the end it says the process could take 1000 years. For a complete melt that would be lightning fast – 7.5 to 8 metres per century, or a metre every 12-13 years. We are pushing the system more than 10 times faster than it has ever been pushed before.

See also Gareth Renownden Goodbye coastline: we are beyond the point of no return.