Jomsom is 8,976 ft above sea level, which is 2,736 m. That figure is the surveyed elevation of the landing site itself rather than of the surrounding terrain, which is why it can differ from the height quoted for a nearby summit or village.

How much oxygen is there at Jomsom?

Air at Jomsom is 20.9% oxygen, exactly as it is at sea level, but at about 725 hPa rather than 1,013 hPa — so a breath holds roughly 72% of the oxygen the same breath holds at the coast. That is the equivalent of breathing 15% oxygen at sea level.

How cold is it at Jomsom?

In the International Standard Atmosphere the temperature at 2,736 m is -3 °C (27 °F). That is a modelled figure, not a forecast and not a measurement: a clear Himalayan morning at this height is routinely colder than the model, and wind makes it colder still on exposed ground.

Altitude and oxygen

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Landing site

Jomsom: altitude and oxygen

Jomsom stands at 8,976 ft (2,736 m) above sea level. The air pressure there is about 725 hPa against 1,013 hPa at sea level, so a breath holds roughly 72% of the oxygen the same breath holds at the coast — the equivalent of breathing 15% oxygen instead of 20.9%. Air is still 20.9% oxygen up there; there is simply less air. In the standard atmosphere the temperature at that height is -3 °C (27 °F), which is a modelled figure rather than a forecast — a clear Himalayan morning is routinely colder.

Elevation: 8,976 ft
Effective oxygen: 15%
Air pressure: 725 hPa
Standard temperature: -3 °C

One breath here against one at the coast

Sea level

100%

20.9% oxygen at 1,013 hPa — the reference.

Jomsom

72%

Still 20.9% oxygen, at 725 hPa. The mixture is unchanged; there is less air holding it.

These figures describe the air, not anybody’s response to it. How a person is affected by height depends on the person, on how fast they got there and on how long they stay — a helicopter reaches these altitudes in minutes, which is a different exposure from a trek that takes days. If you have a heart or lung condition, are pregnant, or are travelling with young children or elderly parents, speak to a doctor before you book and tell the operator when you do: several carry supplemental oxygen and all of them plan the ground time around who is on board. Pressure and temperature are from the International Standard Atmosphere, which is a model — the real morning at this height is frequently colder and thinner still.

Flying here

No published route lands here

Nobody sells a packaged flight to this site, which is not the same as it being unreachable.

A landing site with no scheduled route is flown as a private charter, subject to the aircraft, the party and the landing permissions. Ask the charter desk what it would take.

Asked about this site

Jomsom, in detail

How high is Jomsom?: Jomsom is 8,976 ft above sea level, which is 2,736 m. That figure is the surveyed elevation of the landing site itself rather than of the surrounding terrain, which is why it can differ from the height quoted for a nearby summit or village.
How much oxygen is there at Jomsom?: Air at Jomsom is 20.9% oxygen, exactly as it is at sea level, but at about 725 hPa rather than 1,013 hPa — so a breath holds roughly 72% of the oxygen the same breath holds at the coast. That is the equivalent of breathing 15% oxygen at sea level.
How cold is it at Jomsom?: In the International Standard Atmosphere the temperature at 2,736 m is -3 °C (27 °F). That is a modelled figure, not a forecast and not a measurement: a clear Himalayan morning at this height is routinely colder than the model, and wind makes it colder still on exposed ground.

Another site

Check a different landing site

Flying to Jomsom with someone who needs care?

Leave a number. A dispatcher rings back and plans the ground time, the oxygen and the landing around who is on board — the part of a Himalayan flight that gets decided on the phone rather than in a form.