TY  - JOUR
A1  - Totz, Sonja Juliana
A1  - Petri, Stefan
A1  - Lehmann, Jascha
A1  - Coumou, Dim
T1  - Regional Changes in the Mean Position and Variability of the Tropical Edge
JF  - Geophysical research letters
N2  - Recent studies indicate that the tropical belt has been expanding during recent decades, which can significantly influence precipitation in subtropical climates. Often the location of the tropical border is identified using the Hadley cell edge (HCE) or the subtropical jet stream (STJ), but most studies concentrated on the zonal-mean state, thereby missing regional impacts. Here we detect longitudinal-resolved trends in STJ cores and HCEs over 1979-2016 in both hemispheres at a higher spatial and temporal resolution than previous studies. Besides pronounced regional trend differences in both sign and magnitude, we show that winter HCE and STJ variability increased in the Mediterranean region and decreased over the American and Asian continents. Rainfall variability in these regions changed likewise, and most of those changes can be explained by changes in HCE/STJ variability. This highlights the importance of understanding future tropical belt changes both regionally and in terms of variability. Plain Language Summary We applied a new network-based method to detect motion of the tropical climate border with longitudinal resolution. Depending on the longitudinal position, there are differences in both direction and magnitude of the border motion. In addition, we demonstrate that the rainfall variability is increasing in the Mediterranean region and decreasing over the American and Asian continents, which can be explained by the variability of the tropical belt location.
Y1  - 2018
U6  - https://doi.org/10.1029/2018GL079911
SN  - 0094-8276
SN  - 1944-8007
VL  - 45
IS  - 21
SP  - 12076
EP  - 12084
PB  - American Geophysical Union
CY  - Washington
ER  -