Topographic prominence

The Vertical separation or prominence, also called notch depth or relative dip, is a measure of the independence of a summit, mountain or other geomorphic landform. In addition to the dominance it is an important criterion to classify a mountain as such. With a little pronounced survey, about on a ridge or plateau, the Vertical separation is comparatively low, and this is called a secondary peak or a Graterhebung.

Definitions

• The Vertical separation S of a summit is the difference from its height and the highest Einschartung (reference notch, English:. Key col) to which you have at least descend to reach a higher peak.
• The prominence of a summit is its height above the lowest closed contour ( contour line ) that surrounds him, but at the same time no higher summit.

The two definitions are equivalent.

The concept of relative dip was presented by Klaus Hormann 1965. Since then, the concept has been refined and expanded.

By convention, the saddle height of the highest mountain on earth, Mount Everest, set according to its height above sea level to 8848 m. Corresponding to the gap height of Mount Everest and the sea is regarded in this sense as a saddle. Thus, the definition is extended to the highest mountains of the continents outside the Eurasian landmass and islands: If you imagine that the sea level so long as increases until the peak in question is separated by the waters of all the higher peaks, so the saddle height is just the height of the resulting island bearing the summit. With the exception of the highest mountain of a land mass exists for every mountain just a reference notch. Conversely, each saddle apply only to a certain mountain as a reference notch.

A normalized ( scaled ) value derived is the Orographic dominance, which is the saddle height in relation to height.

Reference mountains

Apart from the Mount Everest, there is every peak beyond the relevant saddle (including the sea ) to reach at least a higher mountain. Some of these mountains with certain characteristics are variously listed as a special relation mountains for the prominence of that summit. In the predominantly English-language literature, they are called Parent Mountains. Some common concepts are presented in the following.

While every mountain has exactly one reference notch and each saddle is reference embrasure for exactly a mountain, more mountains can have the same Parent Mountain.

Examples

• In order from highest mountain in Austria, the 3798 m above sea level. A. Grossglockner high to reach from a higher mountain, you have to stay at least until the Brenner Pass ( 1,370 m above sea level. A. ). From the corresponding altitude is the difference a saddle height of 2428m. Thus, the Grossglockner the second most prominent mountain in the Alps. The following in a potential ridge line next higher mountain, which can be reached via the Brenner Pass without having to descend deeper ( Line Parent), the 3905 meter high Ortler in South Tyrol, which has a lower saddle height with 1953 meters as the Grossglockner is itself next higher geographical neighbor of the Grossglockner in a straight line ( dominance) is the Ortler the adjacent 3851 -meter high peak king, in the ridge line, however, is seen from the Brenner Pass from behind the Ortler. The Prominence master and Iceland Parent of the Grossglockner, the Mont Blanc, which is with 4810 meters the highest mountain peaks.
• The second highest mountain in Austria, the 3768 m above sea level. A. Wild high peak in Tyrol, the Grossglockner in height stands after barely. She shares with this though the Iceland Parent ( Mont Blanc ), but her Master is the Prominence Finstaarhorn ( 4'274 m above sea level. M. ) in the Bernese Alps, to the one on the acting as a reference col 1507 m slm high Reschenpass arrives. The prominence of the Finsteraarhorn is with 2279 m straight between the Glockner ( 2428 m) and the wild- peak ( 2261 m). The prominence of the saddle Finsteraarhorn lies at an altitude of 1,995 m above sea level. M. at the Simplon Pass. Mont Blanc, Grossglockner, Finstaarhorn and Wild top are the four most prominent mountains in the Alps.
• The Prominence master and Iceland Parent of Mont Blanc is the highest mountain on earth, the 8848 meter high Mount Everest in the Himalayas. The geographically next higher mountains are, however, in the past much closer Caucasus. The Elbrus ( 5633 m) obvious Kjukjurtlju ( 4912 m) is dominance reference for mountain Mont Blanc.
• Example of the discrimination rule by Peter Ridges: The Zugspitze is the Fern Pass as a reference notch. The ridge beyond the reference notch runs north of the Inn River to the west to a possible Prominence Parent. North of the Innquelle branches of the comb to the candidate Finstaarhorn and Piz Bernina - both higher and more prominent than the Zugspitze. Piz Bernina is located in the ridge line, although much closer, but the crest of the branch to the Piz Bernina has the 1815 -meter-high Malojapass its lowest point. This height must be no longer below the ridge of the branch to Finstaarhorn, so the Finstaarhorn can be determined as Prominence Parent of the Zugspitze.
• To get from the Great dogbane ( 2593 m) in the Berchtesgaden Alps to a higher summit, one must at least up to Dießbachscharte descend ( 2119 m) ​​, on the one eg for Schönfeldspitze ( 2653 m) or Selbhorn ( 2,655 m ) can reach the stony sea. So here there is a Vertical separation of 474 meters. This is also seen that the saddle height so do not force the height of a summit over that saddle corresponds to that leads to the nearest higher mountain. Because the nearest higher mountain is in this case the watzmann ( 2713 m), but you have to get to this, descend to 1774 meters above sea Trischübelpass even further. The Prominence master and simultaneously Iceland Parent for the Great dogbane is the High King, which has the highest mountain in the Berchtesgaden Alps, the largest Vertical separation in the Northern Limestone Alps and therefore is also one of the most prominent peaks in the Alps.

Independence of mountain ranges, mountains and peaks

Mountain classifications

Hormann has to geomorphometrischen classification of mountain ranges, the measure of the relative dip developed ( see table). Unlike mountains, the aforementioned definitions are not the same because a mountain range does not have to be surrounded by a closed contour line (or one that does not contain higher peaks ): Here, the prominence of the group is always the prominence of its highest mountain on the highest notch their boundary line.

In fact, such systems have not enforced in mountaineering because the groups - to be determined except metrically precise - have little if any benefit. In particular, the divisions so obtained are little coextensive: Thus we find in the Alps under the ten mountains with the highest prominence of the High King (Group Berchtesgaden Alps and Dientener mountains ) a very small in comparison to the other dominant groups group, and among the 13 mountains with saddle height of more than 2000 m to the Santis ( Alpsteinarea ) another.

High mountains

In the Alps is according to a decision made by the UIAA definition of a collection as the pinnacle when their saddle height is at least 30 meters. To speak of a separate mountain at a summit, a minimum of approximately 100 to 300 meters Vertical separation are called for the Alps. In the Himalayas are found as the value of even 500 meters.

For the world as 1500 mountains with a saddle height of more than 1500 meters (of which there are 44 in the Alps) is found in the English literature the term Ultra Prominent Peak.

About the objective criteria such as dominance and prominence of addition but also subjective factors for designation as mountain are determining in practice. So can be crucial as the alpine importance, the view from the summit, the optical dominance from the valley or the entry on a map that a collection is called a mountain. So there are both known and alpinistically significant peak points with very low saddle heights and vice versa mountains that are not even named, despite high autonomy.

Mountain

Even in the Middle Mountains, Vertical separation is used to determine the independence of Bergen. This will entail reprogramming of the numbers required as the height differences are lower there than in the high mountains and wind gap heights of 300 m are very rare. The minimum size of chart heights are 11-14 meters used for the autonomy of peaks depending on the altitude. However, to date a lack of mandatory values ​​that capture all relevant for Mountain altitudes and are widely recognized. The establishment of uniform minimum standards for height chart an independent central mountain peak is complicated by the fact that the mountains are defined here traditionally about their subjective appearance and commonly no need is seen to make a redefinition of the Vertical separation. Not least because the term Vertical separation is much less well established in literature and general awareness of low mountains than in terms of the high mountains.