Hossein Hashemi
Researcher
Linear and nonlinear trend analyses in global satellite‐based precipitation, 1998‐2017
Author
Summary, in English
Precipitation varies spatiotemporally in amount, intensity, and frequency. Although, much research has been conducted on analyzing precipitation patterns and variation at the global scale, trend types have still not received much attention. This study developed a new polynomial‐based model for detecting non‐linear and linear trends in a satellite precipitation product (TRMM 3B43) for the 1998‐2017 period at a near‐global scale. We used an automated trend classification method that detects significant trends and classifies them into linear and non‐linear (cubic, quadratic, and concealed) trend types in satellite‐based precipitation at near‐global, continental, and climate zone scales. We found that 12.3% of pixel‐based precipitation time series across the globe have significant trend at 0.05 significance level (50% positive and 50% negative trends). In all continents except Asia, decreasing trends were found to cover larger areas than corresponding increasing trends. Regarding climate zone and precipitation trend change, our results indicate that a linear trend is dominant in the warm temperate (77.7%) and equatorial climates (80.4%) while the least linear change was detected in the polar climate (68.9%). The combined results of continental and climate zone scales indicate significant increasing trends in Asia and arid climate over the last 20 years. Furthermore, positive trends were found to be more significant at the continental scale, particularly, in Asia relative to the climate zone scale. Linear change in precipitation (80%) was the most dominant trend observed as opposed to non‐linear (quadratic (11%) and cubic (9%)) trend types at the global scale.
Department/s
- Division of Water Resources Engineering
- LTH Profile Area: Water
- MECW: The Middle East in the Contemporary World
- Centre for Advanced Middle Eastern Studies (CMES)
- Transport and Roads
Publishing year
2021-03-27
Language
English
Publication/Series
Earth's Future
Volume
9
Issue
4
Document type
Journal article
Publisher
John Wiley & Sons Inc.
Topic
- Physical Geography
Status
Published
ISBN/ISSN/Other
- ISSN: 2328-4277