High wind in the mountains can be a real game changer, it can have a profound effect on safety and morale. It can make it feel much colder than it actually is (wind chill effect), and can be unpredictable in direction and speed.

Strong winds, (those over 50-60km/hr), are going to impede your progress, and will significantly increase the risk of you being blown over and injured. In addition, walking into a strong headwind for a number of hours will sap both your energy and morale. Add significant gusting and you will be constantly adjusting your balance, foot placements and forward momentum, all of which can be very tiring.

The speed and direction of the wind can be unpredictable in the uplands. As the moving air is pushed over a mountain range it is squeezed between the mountains and the top of the troposphere, causing the wind to speed up. It is nearly always windier, therefore, on mountain tops than in adjacent valleys. The wind is forced over ridges and through saddles, increasing in speed, and making these places more hazardous in stormy weather. The topography of the valleys and mountains often means the wind can be gusting, swirling about and rapidly changing direction, adding to the difficulties of keeping your balance and stability.

High winds will often make it feel colder (wind chill), this can bring about rapid cooling of the extremities, the head and hands in particular. The effect of wind chill is to increase the rate of heat loss to the surrounding air.  Prolonged cooling can lead to hypothermia and frost nip, both very serious conditions.

Cold and wet weather can be dealt with by adequate clothing and equipment, but strong winds mean you may have to change your plans. Here is our assessment of the effect of wind on your ability to move effectively, and what to do about it.

Wind speed in km/hr Effect on you What should you do?
Less than 20 Negligible Continue as planned
20-30 Unlikely to affect your balance or control. At these windspeeds in winter a temperature of 0C will have an equivalent wind chill of around


Add an extra warm layer.

Prevent small items from blowing loose.

Goggles will be useful in winter conditions.

30-40 You will begin to feel the buffeting effect of the wind. Progress into a head wind will become more laboured. It will be harder to maintain your balance when walking. Keep way from steep and exposed ridge lines. Secure your map and tie down loose clothing and secure toggles to prevent them whipping around.
40-50 Walking will become more difficult. Energy output will be significantly increased. Expect a greater risk of being blown sideways and off balance. Consider changing your route to avoid a head or cross wind. Be prepared to shorten the day. Check companions for signs of hypothermia and frost nip, particularly in winter.

Navigation will become more difficult.

50-60 Walking will become very challenging. There is a strong chance of being blown off your feet.


Link arms with weaker members of your group. Try to move between the worst gusts. Get off the hill by the safest and easiest route keeping away from steep windward drops.
60-70 As above If you must venture out in these conditions then keep to the valley floor.


Russ Mills runs Mountaintrails, a guided hiking and mountain training business based in Dublin, Ireland.

Part I

Before being able to take a compass bearing it is essential to understand the relationship between True North, Grid North and Magnetic North. (Part II, walking on a compass bearing, will follow next month).

The Three Norths

Grid North

Grid North is the navigational term for the northward projection of the north-south gridlines on a map. In Ireland it lies to the east of both True and Magnetic North.

True North

True or Geographic North is aligned with the Earth’s axis and points to the geographic North Pole, the axis on which the Earth is spinning. In Ireland it lies west of Grid North and east of Magnetic North.

Magnetic North

Magnetic North is defined as the direction toward which the north-seeking, (red) arrow of a compass points.  Magnetic North is the northern pole of the Earth’s magnetic field and it deviates from True North over time because the earth’s magnetic poles are not fixed in relation to its axis. The current magnetic north pole is located in the Arctic Islands of Canada and is moving very slowly eastwards. In Ireland it currently lies west of both Grid North and True North.

The relative positions of Grid, True and Magnetic North will vary, depending on where you are in the world.

For the purposes of mountain navigation in Ireland and the UK, True North can be ignored.


Magnetic Variation

Magnetic variation is the difference in angle (in degrees), between Magnetic North and Grid North. It varies from place to place, and with time.

In those countries that do not use a grid system, magnetic variation is the difference in angle between Magnetic North and True North.

When taking a bearing from the map, we initially align the compass with the north-south grid lines, or Grid North. However, the red end of the compass needle is pointing to Magnetic North, and we must make a small adjustment to the bearing for this.

Information on the magnetic variation for a particular area can be found in the margins of the map. To calculate the Magnetic Variation we need three pieces of information from the map. 1) Year of map update. 2) The rate of decrease (or increase) of magnetic variation. 3) The current year.

From this information it is possible to calculate the adjustment applied to the compass bearing.

At the present time in Ireland the magnetic variation should be added when taking a bearing from the map to follow on the ground.

In The Wicklow mountains the current magnetic variation (2017) is 4.0 °


Taking a Bearing

  1. Place the compass on the map so that one of the long lines on the base plate, (or the compass edge, though this is less accurate), is touching both your starting point and target point.  Ensure that the ‘direction of travel arrow’ is pointing towards your target point.     (diagram 1)
  2. Hold the compass firmly on the map and rotate the compass housing until the orienting lines in the base of the housing are lined up with, (running parallel to), the north-south grid lines on the map; and the orienting arrow is pointing north.  (diagram 2)
  3. Take the compass off the map and read the bearing at the index line on the compass housing. This is the Grid Bearing.  (diagram 3)                                                                                                                                                                                                    
  4. Calculate the magnetic variation for your location and add or subtract this from the grid bearing. Adjust the bearing at the index line accordingly. This is the Magnetic Bearing.
  5. Hold the compass in front of you with the direction of travel arrow pointing directly away from you. Turn your whole body until the north end of the needle lines up with the orienting arrow (put red in the shed). The direction of travel arrow is now pointing you towards your target.

Take a compass bearing


Take a compass bearing












Take a compass bearing

To learn more about mountain navigation, or to join one of our very popular Mountain Skills courses, go to:

Mountain Courses



Many of us have an altimeter as an integral part of our mountain watches, but how many of us know the skills of navigating with an altimeter?

Here are 5 tips on how to use an altimeter as a navigation tool.

Before we begin however, a note of caution, altimeter watches rely on barometric pressure to calculate altitude and as the barometric pressure fluctuates so does the altitude reading, and this can lead to serious errors if not addressed.

It is important to re-calibrate the altimeter regularly by re-setting it to the correct reading when a known altitude is reached, such as a summit, col or spot height. Read the height from the map, and adjust the altimeter accordingly. This is particularly important in areas where the pressure may change rapidly as weather systems track across the globe, for example over Ireland and the British Isles. Here adjustments should be made every couple of hours, as and when the opportunity presents itself.


  • Knowing how high you are (absolute altitude)

Knowing how high you are (your altitude) and how far you still have to climb is a great way of monitoring your progress. This is particularly helpful on a long uniform slope with little in the way of landmarks, or when visibility is reduced as clouds descend or when night falls.

In poor visibility, reading off the altitude can indicate if you are at the summit of your mountain, or merely a lower, subsidiary top.


  • Ascent rate

Checking your ascent rate is a great way of monitoring your progress. By checking both your increasing altitude and the time taken you can estimate your arrival time at the summit.

For example, if you have a 1,000 metre climb to undertake, and you have completed the first 200 metres of ascent in 30 minutes, then it should take you another 2 hours (4 x 30 mins) to reach the summit. You can check your progress against the estimated arrival time, and if all is going well, reach the summit. Equally, you can re-assess your plans or turn back if you are falling well behind the clock.


  • Descending a slope

Navigating with an altimeter (1) If you are descending a slope, perhaps in poor visibility, and you are required to make a change of direction to avoid steep and craggy ground, check the map for the height at which you need to turn off and when your altimeter reads that height, you can make the necessary change. (In the example below this is at the 790m contour).

This technique would work equally well if you were ascending a slope and needed to change direction.




  • Traversing (Contouring)

Maintaining the same height as you traverse around a slope, (following a contour line), can be notoriously difficult in bad weather. There is a strong tendency to lose height as you go, and drop down the slope.

Checking that the altitude reading on your watch remains constant allows you to maintain your height and traverse the slope without any problems.


  • Relocation (Aspect of Slope)

Navigating with an altimeterIn a previous blog on relocation techniques, I explained how to use your compass to determine the aspect (direction) of slope and thereby determine what side of the hill you were on:

Feb 2017 Relocation Techniques in Navigation)

This navigational technique can be combined with an altimeter reading to determine your exact location on that slope. In the example below the altimeter reads 600 metres, which places you at the red cross on the map.



Used in combination with other navigation skills, and your map and compass, an altimeter can be a valuable addition to your navigation toolbox.

This is a lament we hear often at Mountaintrails, sometimes spoken in frustration, sometimes in anger, and most often at the end of a wet day.

So why is our precious waterproof clothing failing to perform? In many cases it is because we are simply asking too much of it.


The techi bit….

So called ‘breathable’ fabrics have a micro pore membrane bonded to a hardwearing outer layer. This membrane allows water vapour to pass through, but not liquid water. This in turn means that the moisture you produce when working hard is allowed to escape, whilst preventing rain from penetrating your garment.

The ‘breathability’, or Moisture Vapour Transmission Rate (MVTR), is measured in laboratory conditions over a 24 hour period. Manufacturers can then make claims about their materials based on these results.


The problem…

The issue is we are not in a laboratory, we are slogging our way up a damp hillside, and our own transmission rates vary considerably, depending on our activity levels and metabolism, amongst other things.

Exercise vigorously on a wet and humid day and your body will pump out a lot of moisture, much more than the ‘breathable’ fabric of your waterproofs can cope with. Water vapour will condense on the inside of your jacket and your clothing will begin to feel damp. You might think your waterproof is leaking, but it is not, it’s coming from you.

For the water vapour to escape effectively it is important that the outer surface of the material is not saturated with water. To prevent this your jacket is treated with a DWR coating (Durable Water Repellancy), but this coating wears off over time and needs to be replaced. If your jacket is no longer ‘beading’, i.e. the water is forming into small droplets and running off the surface, then it is likely to become saturated, and will ‘wet out’.


This will slow the MVTR and lead to more condensation on the inside of your clothing.

In addition, humans are not well designed for waterproof layers, any clothing has to have holes in it to accommodate our head, hands and legs, and water can enter through these holes resulting in us getting even wetter!


So what can we do to try and stay dry…?

First and foremost, don’t wear your waterproof jacket if it’s not raining. I see so many waterproof jackets being used solely for insulation and wind proofing, and this leads to a build-up of condensation as described above.

Far better to wear a ‘softshell’ jacket. This is essentially a jacket that offers a degree of insulation, can be fully windproof, and will allow moisture to pass through, (in both directions). None of your moisture will condense on the inside and you will feel much more comfortable. Some softshell jackets are designed to keep out a light shower, but might be less ‘breathable’ as a result. The Buffalo is a good example of this.

However, when it starts to rain you must exchange your soft shell for your waterproof shell.


Don’t overheat…

If you have to put on your waterproofs then be sure to remove a layer first, by adding an extra layer you are adding more insulation and will be getting warmer. This will lead to more water vapour being produced by your body and will put extra pressure on the waterproof membrane to perform, resulting in more condensation inside your clothing.


Wash and reproof your jacket regularly…

Waterproof clothing


When the DWR layer wears off and the rain water no longer ‘beads’ on the outside of your jacket it will become saturated or ‘wet out’.

This layer of water on the outside of your jacket will impede the movement of water vapour through the membrane, and more condensation inside your clothing will result, making you feel wetter.

Reproof your waterproof clothing with NikWax Wash-In, or a similar product, on a regular basis. The more you use your jacket the more often you should treat it.



Check on the build quality of your jacket and pants…

The material may be waterproof but rain can still penetrate through seams, pockets, zips and those large openings for your head and hands!

Check that the seams are sealed, or ‘taped’, some top end jackets now have welded seams.

Consider waterproof zips when you purchase your waterproofs, these are much better than conventional zips, though more expensive.

Make sure the hood fits well around your head and can be pulled in tight without impeding vision. Check that the cuffs are adjustable, and can be closed down with Velcro to reduce water ingress.


Avoid cotton T shirts and underclothes…

Cotton will absorb up to 25 times its’ own weight in water, and the hollow fibres of cotton won’t release it easily, so it stays with you and makes you feel cold and clammy. In colder conditions this can also increase the risk of hypothermia.

By wearing synthetic wicking layers the moisture your body produce will be moved to your outer layers and away from your skin, making you feel much more comfortable.


It is not possible to stay completely dry when battling through horizontal rain on a windswept mountain, but by caring for your waterproof clothing and using it appropriately you can stay comfortable, if a little damp, even in the worst of weather.


Russ Mills – Mountaintrails


As summer advances ticks are becoming more active, and more outdoor enthusiasts are finding these unpleasant critters embedded in their skin.

To understand the importance of avoiding being bitten, here are our Top Ten things you should know about ticks:

1.  Ticks are arachnids, and related to spiders and scorpions. They have a 3-stage life cycle, larvae, nymph and adult. At each stage they need a blood meal to grow, ticks feed on small mammals, deer and sheep and will bite humans. They are most active in late spring and summer.

Ticks life cycle


2. Tick bites do not hurt, therefore you will not know if one has bitten you. They prefer warm and damp parts of the body, particularly the hairline, navel, waist, groin and behind the ears and knees.


3. Initially ticks can be very small, about the size of a poppy seed, but will swell as they become engorged with blood. If you find a tick on you or one of your children do not pick, scratch, burn, drown or squeeze it, as it will vomit it stomach contents into your blood stream and pass on any infections it may carry.



4.  Ticks generally do not feed for the first 24 hours, so you have time to check yourself in the shower when you get home.


5.  To remove an embedded tick use a specialised tick removal tool, either a ‘tick hook’ or a ‘tick lasso’. Narrow end tweezers will also help, but remember to grab by the head, and not the body.


6.  Ticks carry a bacterial disease called Lyme borreliosis, or Lyme disease, not all ticks carry it, they get it by sucking the blood of infected animals.


7.  Around 50 -100 cases of Lyme disease are reported in Ireland each year, if you think you are infected you should see your GP, who will run tests to determine whether you have Lyme disease and whether to give a course of antibiotics.


8.  Symptoms may appear after 3 or 4 days, but may take several weeks to appear. Common symptoms are a bullseye rash at the site of the bite, and flu like symptoms, headache, fatigue and fever.


ticks rash

9.  Regular campers, hikers and fishermen are most at risk, and these groups would be wise to carry a tick removal device with them.


10.  Ticks climb tall foliage and drop onto animals as they brush past. To avoid being bitten stay on tracks and paths and away from bracken and other tall foliage in the summer. Wear long sleeves, and particularly long trousers, and tuck trousers into socks or wear gaiters. Applying insect repellent to clothes will also help.

Russ Mills runs Mountaintrails, a guided hiking and mountain skills training enterprise based in Dublin, Ireland.

To learn more go to our website at mountaintrails.ie.

It’s a cliché to say we have become reliant on technology, and we certainly need a map and compass, and perhaps a GPS system, to find our way around unfamiliar hills.

But how did our ancestors find their way around, and what natural features did they use to navigate across the land in times gone by?

Here are 5 ways in which our forebears may have navigated around the landscape; and though we don’t suggest you leave your map and compass at home, it might be fun to try these out sometime, and see if you can navigate like the ancients!

Navigate by the Sun

We all know the sun rises in the east, but in reality, due to the complicated relationship between the Earth and the Sun, this only happens on the equinoxes, in March and September. In the middle of June it will rise in the northeast, and in December in the southeast.

However, it is possible to use the sun to determine the cardinal points (North, South, East, West) by using a ‘shadow stick’. To do this you need a stick around a metre long a handful of pebbles and a sunny day.

Push the stick upright into the ground and mark the end of its shadow with a pebble, now hang around. Every 15 minutes or so mark the end of the sticks shadow with a pebble, and after an hour a distinct line of pebbles will become apparent. The first position of the shadow is the western end of the line, and this line is aligned west to east, allowing you to determine the cardinal points for East and West, and those at right angles to that line, North and South.


Navigate by the Moon

It is possible, when in the northern hemisphere, to find south by observing the Moon. Look up at the Moon when it is waxing or waning, (this does not work when there is a full Moon), and draw an imaginary line between the ‘horns’ of the crescent of the Moon. Continue that line down to the horizon, either by eye or by holding a straight object up to it.

The position on the horizon where this line falls is South.


Navigate by the stars

The details of how our ancestors navigated by the stars may seem complex to us now, but perhaps the easiest piece of stellar navigation is this method of locating North.

Natural navigation - using the stars

Many of us in the northern hemisphere can recognise the constellation Ursa Major, or the Plough, it’s the one with the distinct saucepan outline.

By locating the outer edge of the ‘pan’ we can draw a straight line, about 5 times the distance between these outer stars, and here we will find Polaris aka the North Star.

The North Star sits directly above the North Pole on Earth, and so enables us to find the direction of North.


Navigate by using plants

Plants will always grow towards the sun, and a tree will always have heavier and more luxuriant growth on its southern side rather than its northern side. To see this effectively you need to find an isolated tree growing alone, in a wood the trees are crowded for space and this effect is overshadowed by the need to compete with each other.

Certain lichens and mosses prefer sun to shade, and can often be seen growing on the southern side of large tree trunks, this can be quite reliable when seen on a number of trees growing together.


Navigate by the wind

The prevailing wind, (the direction the wind predominantly blows in), can be determined for your location. In Ireland the winds are generally westerlies, and in exposed areas trees will be ‘raked’ by the wind and will grow bent and downwind. By observing the shapes of these trees it is possible to estimate where West is.

The wind does not change its direction a great deal during the course of a day, unless a frontal system passes though, and this is usually easy to spot. So it could be possible to navigate using the feel of the wind on your face, or the direction it is blowing the grass and other vegetation. However, in hilly areas the wind can swirl around the peaks and saddles, so this may not be so reliable in the mountains.


Russ Mills runs Mountaintrails, a guided hiking and navigation training business based in Dublin, Ireland.

You may wish to learn to navigate using the more familiar methods of map and compass. If so, check out the navigation courses on our website: Mountaintrails Navigation Courses

I was recently asked to produce a list of essential kit for hiking in the mountains (outside of winter), and I have reproduced it here, with some expanded explanations.

The list is not comprehensive, and you may have a few items that you never leave home without to add to this list:

  • Rucksack

A pack of 30 – 35 litres capacity is best, and would be sufficient for carrying what you would need for the day.

  • Rucksack liner or cover

My preference is always for a liner, a waterproof bag that sits in the main compartment of your pack and helps to keep the contents dry in wet weather. Rucksack covers have a tendency to come off in high winds and can be awkward to manage.

  • Waterproof drybags

Put those items that you want to ensure stay dry into drybags for extra protection form the weather.

  • Waterproof Jacket & Pants

Invest in a good waterproof jacket and waterproof pants. These are essential items to ward off both rain and cold winds. Inadequate protection from either can make you uncomfortable at best, and at worst can lead to hypothermia, as the chilling effects of wet clothes and high winds are greatly increased.

Choose one with a breathable membrane to reduce moisture building up inside, and ensure it has either waterproof zips or storm flaps to cover the zip, this will prevent water ingress through the front. Make sure it has a good hood too, with plenty of volume, and that this is adjustable.

  • Gloves

Take several pairs. I am often finding lost gloves and hats in the hills, so take spares to use in case you lose one. It’s also great to change into dry gloves half way through a wet day. Fleece type gloves are ideal for most conditions, but be prepared to upgrade to insulated and waterproof gloves in the colder months.

  • Warm hat

Brightly coloured beanies are the order of the day here, but remember to take a spare in cold weather.

Map and Compass – Essential items that you should know how to use.
  • Map and compass

Essential items for all hillwalkers, do not rely on smartphone apps as phones can get wet and cold and then fail. Carrying a map and compass is not enough on its’ own, you need to be confident and competent in their use. If you are not sure how to navigate yourself around the mountains with a map and compass then go on a course to learn how to master these essential skills.

  • Warm spare layer

You may have an enforced stop in the mountains, maybe a colleague has an injury, or perhaps you are stopping for lunch in an exposed spot. In this scenario a spare warm layer is ideal. A synthetic insulated jacket is best, it can be put over your existing clothing, including wet waterproofs, and will warm you up straight away. A fleece jacket could be an alternative, but they are not windproof, so you would need to put it on under your windproof layer.

  • Food and Drink

Always ensure you have plenty of high calorie food available, and bring extra in case you are delayed and have to spend more time outdoors, a 75kg person with a day pack can burn around 450-500 calories an hour when hiking.

There is no rule concerning how much liquid you should take, though 1.5 litres is a good guide. Take more in hot weather, and take a hot drink in a flask when it is going to be cold. My favourite is a hot fruit tea with honey.

  • First Aid Kit

A bare minimum would be an ‘ouch-pouch’, this could consist of sticking plaster, antiseptic wipes and blister plasters, such as Compeed. You may feel you want a more comprehensive kit, but do get training in this case, and do not carry what you are not competent to use. REC (Rescue and Emergency Care) courses are very suitable and widely available. If you are part of a group then a larger, ‘group first aid kit’ should be carried between you.

  • Survival bag

This is rather like a plastic sleeping bag, bright orange, lightweight and cheap, and everyone should carry one in their pack. In emergency situations you can climb into this bag and it will protect you from the worst of the weather. They have often been attributed with saving lives in the mountains.

Group Shelters
  • A group shelter

Also known as an emergency or survival shelter, this is a plastic tent-like cover that a group of people can get into to give protection from the elements. They come in various sizes from 2 to 10 person, and would be used to protect a casualty or as a shelter on an exposed lunch stop. If you are hiking as part of a group then a larger one could be carried between you.

  • Head Torch

Essential in winter, and a good idea all year round, a head torch will provide you with light to get off the mountain should you be caught out in the dark, it can also be used for signalling for help. It’s a good idea to carry extra batteries, or a spare torch in addition.


  • Emergency whistle

Many rucksacks now come with an integral whistle in the chest strap. Six one second blasts on the whistle, repeated after a short break, is the internationally recognised emergency signal. The reply from the rescuers is three blasts. It makes sense to carry one.


Russ Mills owns and runs Mountaintrails, a guided hiking and navigation training business based in Dublin, Ireland 




One of the most important navigation skills is being able to relocate yourself when you have become ‘lost’ or more correctly, ‘temporarily misplaced’. Having the relocation techniques to deal with such a situation is a key element in being a competent navigator.

Firstly, do not panic. Stay calm and stay where you are.

Many people, on realising they are misplaced, will press on more quickly, or walk in any direction in the hope of finding something they recognise, thus making the problem worse.

Have something to eat and drink, this will both give you time to calm down and increase your blood sugar to help you think.

Gather All Available information

What can you see around you? Are any features in view, such as a forest edge or a stream, and what is the shape of the terrain around you, which way is the ground sloping?

How far have you walked since your last known position, (the location where you were last certain of your position). How long did it take you? What distinctive features did you pass, such as a path junction, knoll or forest edge?

See if you can locate any of these features on your map, and use the information to narrow down the possibilities.

Aspect of Slope

If the terrain you are on is sloping it is possible to use this important technique to help you find your position. Use your compass to take a bearing directly down the line of the slope, that is the line that a rolling ball might take, adjust for magnetic variation, and then search the map for slopes with that aspect.

Mountain Navigation - Aspect of slope

In the example above, if we know we are somewhere in the vicinity of hill 668, and we take a bearing down the slope of 198°, then we can eliminate all slopes that do not have that aspect.

With our bearing set on the compass, we can line up the orienting lines in the compass housing with the north-south grid lines on the map. By moving the compass around the map we can locate the slope(s) where the long edge of the baseplate is pointing directly down slope, (and is at right angles to the contours).

We can now locate ourselves somewhere on the southwest slope of hill 668.

Back Bearings

If you have been walking on a bearing, and the indications are that it was incorrect, then it is still possible to return to your last known position.

Instead of walking with the red end of the compass needle aligned with the orienting arrow, (keeping red in the shed), turn yourself through 180° and align the white end of the compass needle with the orienting arrow, (put white in the shed).

Following this bearing and remembering the paces, or time it took, you can return you to your previously known position. This will only work if you did not stray wildly off the original bearing, or wander around the hill hoping to see something you recognised.


Resection can be a time consuming process. It also relies on the fact that you can see far enough to identify two, and preferably three, major features that are also on the map such as hill tops or stream junctions.

It could be argued that if you can identify these features then you are not misplaced! However, under certain circumstances it can be a useful technique. If you are somewhere along a long, featureless ridge for example, and need to pinpoint your position more accurately.

Mountain Navigation - Relocation


  1. Take a compass bearing to a feature, and after converting it to a grid bearing, place one of the top corners of the compass baseplate on the feature identified on the map.
  2. Carefully manoeuvre the compass until the orienting lines in the housing line-up with the north-south grid lines on the map, being sure to keep the corner of the baseplate on the feature and the orienting arrow pointing north.
  3. Your position now lies somewhere along the long edge of the compass base plate, you can now plot this line on the map using a pen, (see red lines above).
  4. Repeat this for one or more features to pinpoint your position, depending on the accuracy with which you took the bearings your position will lie at the intersection of these lines.


Article by Russ Mills – Mountaintrails

These, and other navigation techniques, can be found in ‘Navigation in the Mountains’, published by Mountain Training and available through our website shop here:


Hypothermia occurs when the core temperature of the body falls below 35°C.

Exposure Hypothermia occurs over several hours following exposure to moderate cold. The casualty becomes exhausted and then cools rapidly as their energy reserves are depleted and they are no longer able to shiver to re-warm themselves.

Immersion Hypothermia occurs where the casualty has had a sudden immersion in cold water or snow, the cold rapidly overwhelms heat production. Although rarer in the mountains, it can happen if someone falls in an icy stream.


Main Causes and factors

Hypothermia occurs when a body loses heat to the environment faster than its ability to generate heat.

Weather – wind and rain in combination will decrease the body’s temperature rapidly due to the effect of wind-chill. This means that even on a relatively mild day, it is possible to succumb to hypothermia if it is windy and raining. The colder the air temperature, the higher is the risk.

Clothing/equipment – A lack of suitable waterproof clothing will lead to clothing layers getting wet, which will increase heat loss considerably. A wet body losses heat 20 times faster than a dry one. Waterproof jacket and trousers as well as at least two decent insulating layers such as a fleece or synthetic belay type jacket are important in trapping heat and cutting out wind-chill. The body can also lose substancial amounts of heat through the head, so a hat is a must.

Dehydration and lack of food – The body needs food and drink in order to metabolise effectively and efficiently. The energy released by our metabolism heats our body, if our fuel reserves are depleted then we cannot produce the heat we need to stay warm.

 Ill health – People who are ill may be less able to metabolise and generate heat, and so are more likely to chill quickly.

It is always colder on the mountain than in the car park..!


There are several ways of classifying hypothermia. Perhaps the easiest is to think of hypothermia in terms of mild, moderate and severe. However, it must be noted that different people exhibit different signs before others, and not all the signs and symptoms may be present in everyone.

Mild Hypothermia

At this stage the body still has resources of its own to try to fight the effects of the cold, shivering will occur which is a voluntary response of the body to re-warm itself. Asking the casualty to stop shivering is a good test, if they can then the hypothermia is mild.

Mild hypothermia can be treated quite easily. Stop, find shelter, put more layers on and get high energy foods and warm drinks into the casualty. The food needs to be high energy e.g. a Mars Bar or glucose gels to help fuel the body’s production of heat. The casualty should then be able to walk off the mountain without any extra help from the emergency services.

Moderate Hypothermia

If, on asking, the casualty cannot stop shivering, they are in the realms of moderate hypothermia. By now the body’s energy resources are depleted and it has no way of reheating. The brain itself is affected and people act out of character with the ‘Umbles’. Speech may become Mumbles, they Stumble as they lose co-ordination, they may become irritable and Grumble, their ability to do small tasks such as do up their rucksack or close zips on their clothing will reduce to Fumbles.

Confusion occurs and sometimes a casualty maybe under the illusion that they are warm and start to strip clothes off. While the casualty is still conscious it may be possible to re-warm by extra layers and warm clothing. However around these temperatures, the heart is in danger of fibrillation and the casualty may collapse and become unresponsive.

Severe Hypothermia

32°C and below, the casualty is in a serious way. Their heart is now in serious danger of ventricular fibrillation, this is an abnormal heart rhythm where the heart muscles contract in an uncoordinated manner out of rhythm with each other. This is life threatening and can be caused by the shock of cold blood rushing into the heart if the casualty is moved roughly.

The severely hypothermic casualty now has a cooled brain and so their usual functions will disappear. It may be difficult to detect signs of life as the muscles become more rigid and so pulses may not be found. The body falls into a dormant like state and breathing may be so shallow and slow that this too may be undetectable, the casualty’s eyes may not react to light and may be dilated.

Mountain shelter, blizzard bad and survival bag.

Prevention of hypothermia

  • Check the weather forecast and make sure that you are adequately equipped for the conditions. Even if the forecast is good, conditions can change rapidly in the mountains, particularly as you gain height. When it’s chilly in the car park, it will surely be considerably colder at 900 metres.
  • Make sure you have adequate clothing, waterproof trousers and jacket and spare warm layers. Folks generally overestimate the effectiveness of their gloves. Ensure you have insulated winter gloves and a warm beanie hat to wear. Take spare gloves in case they get wet or lost.
  • Carry a survival bag, or even better a blizzard bag to wrap yourself or the casualty in an enforced stop or emergency. This will help to retain body heat.
  • A mountain shelter is a great addition to your winter kit, it will provide protection form wind and rain and can become quite warm and cozy if you have several occupants.
  • Take plenty of high energy food and preferably a hot drink.
  • Plan an appropriate route for the conditions and make sure that you can navigate using a map and compass so that you do not become disorientated in poor weather conditions.
Full on winter on Lugnaquilla mountain.


A summary of symptoms, signs and treatment of hypothermia:

Mild Symptoms

  • Shivering, cold, pale skin
  • Paleness/blueness of lips and extremities
  • Fast breathing
  • Lethargy

Mild Treatment

  • STOP! Seek shelter
  • Extra layers
  • Food & hot drinks (although often it is said that caffeine should be avoided because it is a diuretic, if it is the only hot drink available then it will still help the casualty)

 Moderate Symptoms

  • Uncontrollable and violent shivering
  • Pale, cold skin
  • Blue lips
  • Slurred speech
  • Lack of co-ordination
  • Stumbling
  • Confusion
  • Loss of motor skills
  • Fumbling of easy tasks
  • Irrational behaviour (e.g. stripping off clothes)

Moderate Treatment

  • As for mild hypothermia
  • Monitor carefully
  • If the casualty stops shivering, check that they really have warmed up before deciding to walk off, i.e. are they looking warmer, do they feel warmer to touch? Is their skin pinker? Are they back to their usual character? (Because casualties also stop shivering in severe hypothermia).

Severe Symptoms

  • Shivering ceases
  • Cold, pale skin
  • Blue lips
  • Dilated pupils and not reacting to light
  • Unconscious and unresponsive
  • Muscle rigidity
  • Breathing and pulse may be undetectable

Severe Treatment

  • 999!!!
  • Move as little and gently as possible
  • Insulate from ground and air with as many layers as possible (but do not make big movements of the casualty)
  • Glucose gels smeared on the gums might possibly help, however, do not try to force feed an unresponsive casualty!
  • Shelter
  • Do not do CPR (you may not be able to detect the pulse and breathing although it may be present) N.B. a casualty is never cold and dead, only warm and dead
  • Protect the airway; Safe Airway Position


Russ Mills runs Mountaintrails, a guiding hiking and skills training business based in Dublin.

Autumn is definitely upon us, the clocks go back at the end of his week, reducing the amount of available daylight in the evenings.

Despite the gathering gloom and the cooler days, autumn also brings with it some great opportunities for the hiker and mountaineer.  The quality of the light becomes magical, and the golden glow from the sun is reflected back by the russet yellows and browns of the autumn leaves. Descending a hill at sunset, with crisp clear air and a stunning sunset is a special moment to savour.

But as the seasons march on, and autumn turns cooler, the weather in the mountains becomes more unpredictable. It gets a lot colder as you gain height, and a cool day in the valley can become an icy blizzard on the high tops.  To keep comfortable and safe in these conditions there are a few items of cold weather gear we need to add to our rucksack.

Head Torch

Remember, the clocks go back one hour at the end of October, and as a result it gets dark much earlier, at around 17.00. This seems to catch out unwary hikers every year, and the Mountain Rescue organisations are constantly reminding us to carry a torch.  Being caught out in the mountains in the gathering darkness can be an unnerving experience for those not used to hiking and navigating in the dark. Don’t be the one surprised by the shorter daylight hours and be sure to carry a torch, preferably a head torch, with spare batteries.

Hat and Gloves

Seems obvious doesn’t it?

Lightweight summer gloves won’t cut it in the cold wintry winds that rake the summit ridges at this time of year. Make sure to upgrade your gloves to take account of this, a waterproof fleece lined pair are best.  Remember to take spares too. If you lose a glove, (and I am forever finding odd gloves lost in the hills), your hands can become painful and numb and you will lose dexterity and be unable to perform basic tasks.  I am often replacing clients thin gloves with warmer ones once out in the hills, as they begin to feel the cold.

My favourite combination would be a pair of light liner gloves coupled with fleece over gloves, and a pair of winter gloves in the pack just in case. With my spare fleece gloves that makes four pairs in my kit!

Don’t forget your warm beany hat; you can lose a lot of heat from your head on a cold day. Acrylic, ‘thinsulate’ or wool materials all work well, just make sure it’s brightly coloured!

Spare warm layer

It’s a good idea to pack an extra warm layer to put on when you stop for lunch or get delayed. This might happen if there is an injury to one of your party or if you are forced to rest in an exposed position.  This could be a fleece jacket that you put on under your waterproof. Remember that fleece is a good insulator but is not windproof, so is ineffective as an outer layer in windy conditions.

I prefer a lightweight synthetic insulated jacket with a windproof outer layer. This works just as well when wet as it does dry, and can be put on over your existing wet jacket if necessary.

Waterproof shell clothing

You will be carrying your waterproof jacket already, but at this time of year it can be really put to the test, so make sure it is clean and re-treated before the autumn storms set in.  Don’t forget to pack waterproof pants too, if the rain is running off your jacket it will soak your legs if they are not equally protected.

Boots and gaiters

Make sure your boots are up to the task.

Fully waterproof boots are essential at this time of year, fabric boots are popular as they are light weight and relatively cheap, but they won’t keep you dry over a prolonged period in the boggy ground of Ireland.  If you can, upgrade to a leather pair, they will last longer and keep your feet warm and dry through autumn and winter hikes for many years.

Wear gaiters to protect the uppers of your boots and to keep the mud and debris off of your trousers.

Mountain shelter or survival bag

A mountain shelter or bothy resembles a large orange tent without any poles. You can throw it over your head and sit on the ‘hem’ to keep it stable.  Inside you will be warm and dry, out of the worst of the weather. You can eat your lunch, take a break, or attend to an injury in relative comfort.  They are an important addition to your cold weather gear, and come in a range of different sizes for group use.

For personal use a survival bag is essential, this is a large plastic bag that you can get into in an emergency to keep you out of the elements. For cold weather use consider a blizzard bag, which is mutilayered with baffles to trap warm are and provide insulation, keeping your warmer for longer.

Cold weather gear

Map and compass

You should always carry a map and compass with you, even if you are familiar with the route.

There is a greater risk of the summits being enveloped in cloud at this time of year, and poor visibility should be expected.  Take a spare map too, in case one gets blown away, and ensure they are laminated, or protect them with a soft map case, as a precaution against the weather.

Don’t rely solely on technology, though there is a place for phone apps and GPS, they are great as a back-up to your map skills, and they should not be used in isolation. These units can fail when they get wet, or too cold, or when the batteries die.

If you are not completely confident in your map and compass abilities then join a Mountain Skills or mountain navigation course to learn the necessary skills.


The cold weather gear above doesn’t weigh as much as you might think, and will keep you safe and comfortable when hiking in the mountains during the colder months.

The reassurance gained from knowing you have prepared for the worst will make it all worthwhile!

Russ Mills is the owner and principle guide of Mountaintrails, a guidied hiking and mountain training business based in Dublin.