Thursday, 29 October 2015

Mapping Mountains – Trimble Surveys – The Calf


10.10.15  Winder (SD 654 932), Arant Haw (SD 662 946), Calders (SD 670 960), Bram Rigg Top (SD 668 964) and The Calf (SD 667 970) 

Arant Haw (SD 662 946)

The Howgill Fells form an extended group on the periphery of the Yorkshire Dales and are sandwiched between the M6 to the west and the flat topped moorland hills of the Dales to the east.  The group of hills which form the Howgills are rather magnificent as they give good walking underfoot on extended ridges with the hills being eloquent in shape.

I travelled north with Mark and met John Kirk in Sedbergh where my diet met its match in the temptation of a scrummy English breakfast, having tackled three sausages and a variety of other rather lovely fattening objects that had all nestled on my large plate and said ‘eat me’, I sat back and wondered why some people think that dieting is difficult.

We parked the cars at approximately SD 652 922 and walked up the continuation of the paved road and headed up toward Winder, our first hill of the day, via the Lockbank Farm and initially steep hillsides eased with walking on green paths. 

On our way up Winder

The day’s weather forecast was good with rain an afterthought, and sunshine hazed with afternoon cloud predicted.  As we crested the upper ridge of Winder the trig pillar and its accompanying topographic viewfinder came in to view, three people were near the trig and another person was slowly walking up the hill’s western ridge to join them.  This family of Mum, Dad and two sons would spend the day being asked to avoid the Trimble on a succession of summits and cols as we came across them on three occasions, they happily took diversions and laughed along with our antics as somewhere during our meeting and the following conversation the term ‘dullness’ was mentioned and this then became a passing joke for the rest of the day.

We planned on visiting five hills during the day and I hoped to survey them all, the first of which is Winder, a Four that is listed with 32m of drop.  The high point of this hill is easily identifiable and as the Trimble gathered its customary five minutes of data I stood back, scribbled all relevant details in my notepad and tried to regain my breath.

Gathering data at the summit of Winder

Our next hill was Arant Haw, which is another smoothly shaped and elegant hill, between us and its summit was the critical col of Winder, we had some debate if this was on, or a few metres to the north-west, of the ridge path, deciding on the latter I set the Trimble up on top of my rucksack and waited for the five minutes of data to be collected.  During this Mum, Dad and the two sons walked toward us, smiled and kindly took a detour around the survey equipment.

Beyond this col lay the summit of Arant Haw and the slow walk up was pleasantly welcome; we rested beside its northern escarpment edge as the Trimble gathered its all-important data.  As Mark and John ate their dinner I scampered down the path leading to Calders and quickly set the Trimble up at the next col.  By the time data were collected John and Mark were walking on the path just a minute or so from the set-up position.

Winder from the ascent of Arant Haw

The beautiful smoothed land of the Howgills

Gathering data at the summit of Arant Haw

As we slowly plodded our way up the southern ridge of Calders John decided to head back as he had a meal to prepare for this evening and we all know that food is much more important than the hills, so off he dashed, and Mark and I plodded on.

The summit and critical col of Calders has been surveyed by Alan Dawson with his Leica RX1250, therefore this was not a priority for me today.  However, if time permitted I wanted to get a data set at the summit to check the Trimble’s processed height against Alan’s Leica equipment.  And if there was enough time the same could be done at its critical col, and this was scheduled as the last survey of the day depending on time and inclination.

The summit of Calders is a small embedded rock on the side of the path approximately 5 metres from the base of the hill’s summit cairn, as the Trimble did its stuff Mark went ahead to assess the next col on our route.  This col connected to Bram Rigg Top which is listed as a Nuttall with just 15m of drop.  As this is the minimum drop to qualify for John and Anne’s list of English 2,000ft mountains it meant that the Trimble survey was one of the most important of the day.  However important I judged this survey to be, it had not been pencilled in prior to the walk and had only been spotted by Mark as he consulted its drop value on Hill Bagging as we were getting our boots on in Sedbergh.

Gathering data at the summit of Calders

I was soon with Mark down at the col and set the Trimble up where we judged its critical point to be placed, this was a few metres from the gravelled path and adjacent to a drainage pipe inserted under the path which may indicate that this is the low point of the path hereabouts.  This pipe fed water away from a ditch which was lower than the Trimble set-up position and which we had dismissed as being man-made.  After the allotted five minutes of data were gathered we headed up to the hill’s summit.  This hill has a small cairn placed at or near to its high point, we both independently judged the summit of the hill to be approximately 10 metres from this small cairn.  The cairn is now placed on solid ground, whereas our preferred high point was amongst moor grass which can be deceptive as on occasion its height can give a false sense of elevation.

Bram Rigg Top in the background, gathering data at its critical col

Calders in the background, gathering data at the critical col of Bram Rigg Top

As the Trimble gathered data Mark sauntered off toward the high point of the day, and the highest summit in the Howgill Fells; The Calf.  I soon packed the equipment away and scampered off to join him.  I’d only been to the summit of The Calf on one occasion, in May of 1992 on a decidedly warm day.  I had good memories of this walk and the impression that these hills had left with me.

Gathering data at the summit of Bram Rigg Top

A more expansive view of the summit of Bram Rigg Top taken from the same position as the above photograph

The view of Calders from the summit of Bram Rigg Top

Gathering data at the summit of Bram Rigg Top

Once at the summit I positioned the Trimble on top of my rucksack and away it went gathering its five minutes of data.  All that remained was the critical col of Calders which was back the way we had just come.  As the Trimble gathered its last data set of the day Mark walked ahead and said that if I hadn’t caught up with him he would wait beside the cairn at the summit of Calders.

The Calf from the descent of Bram Rigg Top

Gathering data at the summit of The Calf

The last of the day's data sets at the critical col of Calders

By now my arms were cold as the easterly breeze had picked up during the late afternoon, I stopped and tried to get my one skin summer walking jacket on and had a bit of difficulty to get my numbed fingers working to zip it up, as I pulled my gloves on heat replenished my hands and I joined Mark on the track heading back over Calders.  All that remained was to re-trace the majority of our inward route back to the awaiting car. 

Looking toward Arant Haw (SD 662 946) on our descent

There is a soft beauty to the Howgill Fells as their sloping ridges fall to green pastured valleys, they evoke friendliness and hospitality with eloquently shaped profiles, and today their beige coloured early autumnal moor grass swayed in the light breeze adding movement to their static form.  They are a lovey hill range and one I hope to revisit again in the future.

The soft rounded ridges of the Howgills

Next stop Mr Kirk’s for a yummy Paella.

mmmmmmmmm yum yum, looks good
         
LIDAR summit image of The Calf (SD 667 970)

Since the survey of these hills LIDAR has become available.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height and positional data that is now freely available for much of England and Wales.  Consequently the numerical details for these hills have been analysed using this technique, resulting in the LIDAR heights and positions for some of these hills being used in favour of other surveying methods.


  
Survey Result:



Winder

Summit Height:  473.7m (converted to OSGM15)

Summit Grid Reference:  SD 65401 93275

Col Height:  442.7m (converted to OSGM15)

Col Grid Reference:  SD 65784 93722

Drop:  31.0m

Dominance:  6.55%




Arant Haw

Summit Height:  606.6m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SD 66206 94629 (Trimble GeoXH 6000)

Col Height:  550.1m (LIDAR)

Col Grid Reference:  SD 66960 95333 (LIDAR)

Drop:  56.4m (Trimble GeoXH 6000 summit and LIDAR col)

Dominance:  9.31% (Trimble GeoXH 6000 summit and LIDAR col)




Calders

Summit Height:  675.4m (converted to OSGM15, Trimble GeoXH 6000 and Leica RX1250)  

Summit Grid Reference:  SD 67070 96002 (Trimble GeoXH 6000 and Leica RX1250)  

Col Height:  641.2m (converted to OSGM15, Trimble GeoXH 6000 and Leica RX1250)  

Col Grid Reference:  SD 66865 96762 (Trimble GeoXH 6000 and Leica RX1250)  

Drop:  34.2m (Trimble GeoXH 6000 and Leica RX1250) 

Dominance:  5.07% (Trimble GeoXH 6000 and Leica RX1250)




Bram Rigg Top

Summit Height:  672.9m (LIDAR)

Summit Grid Reference:  SD 66830 96464 (LIDAR)

Col Height:  658.2m (LIDAR)

Col Grid Reference:  SD 67034 96281 (LIDAR)

Drop:  14.7m (LIDAR, Trimble GeoXH 6000 and line survey)  (Nuttall deletion)

Dominance:  2.18% (LIDAR and Trimble GeoXH 6000)




The Calf

Summit Height:  676.7m (LIDAR)

Summit Grid Reference:  SD 66746 97042 (LIDAR)

Col Height:  293.6m (LIDAR)

Col Grid Reference:  NY 73223 00646 (LIDAR)

Drop:  383.2m (LIDAR)

Dominance:  56.62% (LIDAR)




For further details please consult the Trimble survey spreadsheet click {here}



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