Trends in Global Tropical Cyclone Activity: 1990–2021
It is important to detect any observed trends in global tropical cyclone (TC) activity to understand the potential influence of climate change during the historical period. Here, we investigate global trends in TC activity over the last three decades, which were marked by largely consistent observational platforms.
Global hurricane counts and Accumulated Cyclone Energy (ACE) have significantly decreased since 1990, driven primarily by a downturn in western North Pacific TC activity, and likely due to a trend toward more La Niña-like conditions. This research indicates that modes of climate variability can play an important role in driving changes in global 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, 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.