The relationship between African dust and the climatology of tropical cyclones (TCs) in the North Atlantic is explored using the Community Atmosphere Model at a global horizontal resolution of 28 km. A simulation in which the aerosol model is modified to significantly reduce the amount of airborne dust is compared to a standard simulation. The simulation with reduced dust increases TC frequency globally, with the largest increase occurring in the North Atlantic. The increase in TC activity in the North Atlantic is consistent with an environment that is more conducive for the genesis and intensification of storms. TCs are more frequent (27%) and on average significantly longer lived (13%) in the low dust configuration but only slightly stronger (3%). This results in a 57% increase in accumulated cyclone energy per hurricane season on average. This work has implications for projections of future climate and resulting changes in TC activity.
This study investigates global tropical cyclone (TC) activity trends from 1990 to 2021, a period marked by largely consistent observational platforms. Several global TC metrics have decreased during this period, with significant decreases in hurricane numbers and Accumulated Cyclone Energy (ACE). Most of this decrease has been driven by significant downward trends in the western North Pacific. Globally, short‐lived named storms, 24‐hr intensification events of ≥50 kt day−1, and TC‐related damage have increased significantly. The increase in short‐lived named storms is likely due to technological improvements, while rapidly intensifying TC increases may be fueled by higher potential intensity. Damage increases are largely due to increased coastal assets. The significant decrease in hurricane numbers and global ACE are likely due to the trend toward a more La Niña‐like base state from 1990 to 2021, favoring North Atlantic TC activity and suppressing North and South Pacific TC activity.
more » « less- NSF-PAR ID:
- 10371590
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 49
- Issue:
- 6
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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