Global distribution of degraded land area based on dust erodibility determined from satellite data

ABSTRACT

Arid regions are highly vulnerable to climate change and human activity. Global warming has the potential to increase their area. In most arid regions, desertification, land degradation, and drought are frequent. An early warning and monitoring system based on numerical models, remote sensing, and weather forecasts is urgently needed to guard human well-being in those regions. This study defined degraded land area on the basis of dust erodibility determined only from satellite data, and measured seasonal variations over each continent. During the 5 years from 2012 to 2016, degraded land area showed a tendency to increase in South America and Oceania and to decrease in Asia, Europe, Africa, and North America. Degraded land area covered up to 19% of the world’s total land area, almost exactly the percentage of hyper-arid (7.3%) plus arid regions (11.6%) determined by the widely used aridity index, and down to 7%.

Acknowledgments

I appreciate invaluable comments by two reviewers on this paper.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

This research was supported by KAKENHI Grant No. 25304037 of the Japanese Ministry of Education, Culture, Sports, Science and Technology.