Chinese scientists have come to interesting conclusions: Despite global warming, the territory of thousands of islands around the world is not decreasing, but on the contrary, growing. This is facilitated by human activities. As global temperatures increase, the melting of glaciers and the thermal expansion of seawater cause ocean levels to rise, posing serious risks for island countries and coastal areas. Against this background, the research of scientists from the Chinese Academy of Sciences, who studied satellite images of islands located in Southeast Asia, the Indian Ocean and the Mediterranean, looks strange. Photos were taken from 1990 to 2020. The scientists’ results were published in the journal International Digital World Magazine.

First, the experts examined the studies of other experts on a similar subject. The investigation of the islands turned out to lead to three conclusions. First, it speaks to the significant coastal erosion associated with sea level rise. This trend is illustrated by the example of the Hawaiian Islands, especially Oahu and Maui. The rate of sea level rise was found to be approximately 65 percent higher on Maui than on Oahu. Coastline erosion also occurs in the Solomon Islands. Analysis of aerial and satellite images taken from 1947 to 2014, recording 33 islands, showed that five small (and therefore uninhabited) reef islands completely disappeared during this time.

Other studies have shown that many island coastlines remain relatively stable despite rising sea levels. A comprehensive analysis of 30 atolls in the Pacific and Indian Oceans, covering a total of 709 islands, showed that no atoll experienced a decrease in land area. Moreover, 88.6 percent of the islands either remained constant or even increased in size, while only 11.4 percent decreased in area.

The third perspective assumes that, despite the rise in sea level, the coastlines of the islands are subject to deposition rather than erosion as their area expands. It is also claimed that large-scale human activity (e.g. beach washing) played a major role in the expansion of islands and prevented the rise of the World Ocean level. This conclusion is supported by a study of 101 islands of the Pacific island of Tuvalu; An increase in land area was observed in eight of the nine atolls studied here.

However, we note that in Tuvalu, unlike other regions, almost no serious measures are taken to wash artificial beaches. Some scientists explain the expansion of Tuvalu by global warming: it strengthens the surf, which carries debris from the seabed to the shores of such islands.

But such studies have problems with methodology, there is a lack of research on this issue, which Chinese scientists decided to correct. They used a standardized data set and quantitative methodology to examine coastline changes on more than 13,000 islands. The total coastline length of the islands reached 196,700 kilometers in 1990, 198,900 kilometers in 2000, 199,500 kilometers in 2010 and 200,200 kilometers in 2020. Approximately 12 percent of the coastline has undergone significant changes.

In the last 30 years, the total land area in the studied region increased by 157.21 square kilometers. However, this trend was uniform. Thus, from 1990 to 2000, the area of ​​​​the islands decreased by 259.33 square kilometers, but in subsequent years the situation changed. The net increase from 2000 to 2010 was 269.67 square kilometers, while from 2010 to 2020 it was 32.67 square kilometers.

The area of ​​the Philippine Archipelago, the islands of South and West Asia, and East Africa decreased overall, but not by more than 30 square kilometers. But the area of ​​\u200b\u200bthe Indonesian archipelago, the islands along Indochina, as well as the Maldives and those located in the Red and Mediterranean Seas, has increased in pure terms. It was also revealed that the Indochina islands hold the growth record of the region.

Scientists called the main driving force of what is happening the reclamation and reclamation of new lands near the sea with the help of the gradual construction of dams and filling of artificial beaches. According to them, the main factors affecting changes in the coastline can be divided into anthropogenic and natural.

The first includes urbanization, aquaculture, port construction, dams, and others. Natural factors include rising sea levels, storm surges, effects of earthquakes, growth of mangroves, etc. takes place. Natural factors had a relatively small impact on the expansion of the coastline.