A stir has been created by the recent finding of Europe’s Sentinel-1A satellite that the 2015 earthquake in Nepal measuring 7.8 in magnitude might have shrunk the heights of several mountains in the surrounding area including that of Mount Everest by about 1 inch.
This observation has led to consternation over whether Mt. Everest’s height really has been altered. It led to several international institutions and India seeking to measure the height of Mt. Everest. However, the Nepalese Government has stated that it shall undertake the measurement of Mt. Everest on its own. Technicians began work on this since the 2nd week of June, 2017 from Udayapur district and work is expected to be completed in two years’ time. A host of international experts and scientists are expected to be involved in the process (Kathmandu Post, 2017). According to the Survey of India, the present height of Mount Everest is 8,848 m, which is the height mentioned in all Indian schoolbooks. The Survey of India also plans to undertake re-measuring of the height of Mt. Everest in 2017.
The first measurement of Everest’s height dates back to 1856, when its height had been fixed at 8,840 meters (29,002 feet). The mountain is named after George Everest – then one of the founders of the Survey of India – that carried out large-scale measurements of the Himalayas.
The period following the first measurement has witnessed a rise in measured results of the height of the world’s tallest mountain. The Survey of India carried out new measurements between 2880 and 1904 under Sydney Burrard, who measured the height at 8,882 meters. However, in 1954, with the advent of new technologies, namely, geoidal rise, atmospheric refraction, deviation of gravity from the normal, and adjustment of erroneous height of the observing stations, B.L. Gulatee carried out a fresh measurement of Mount Everest. Considered a more accurate measurement, the elevation was calculated from sea level and determined the height at 8,848 meters (G. Poretti, 2015).
The geoid is a hypothetical approximation of mean sea level, and is dependent on gravity measurements, which however, becomes less dense with increase in altitude. The measurements therefore, are based on hypothetical determinations based on mathematical criteria and have to take anomalies such as those caused by gravity into account (G. Poretti, 2015). It is not possible to take a direct measurement of Mount Everest from sea level, and one has to rely on such hypothetical mathematical criteria.
The progress of technology has led to improvements in the accuracy with which a mountain’s height is measured. Although, errors are generated with the use of technology and a number of measurements have yielded different measurements of height for Mt. Everest. Other than the aforementioned measurements, some other notable measurements have been carried out of Mt. Everest. These include China in 2005 (8,847 m), Washburn e Chen in 1999 (8,850 m), J.Y. Chen in 1999 (8,849 m), Desio and Caporali in 1987 (8,872 m) and De Graaf Hunter in 1930 (8,854 m) (G.Poretti, 2015). As can be observed, there is considerable variance in the heights of Everest. Even in two separate measurements taken by W E Chen and J.Y. Chen in the same year – 1999 – there is a difference of about 1 meter, that can be considered a considerable difference. These can be attributed to technological techniques considering that sea level cannot be taken into account directly in the measurement of Mount Everest.