Nearshore Hurricane Intensity Change and Post‐Landfall Dissipation Along The United States Gulf and East Coasts

Abstract

Hurricanes undergoing intensification immediately before landfall can cause devastating losses of both life and property. For example, Hurricane Audrey in 1957 intensified from maximum sustained winds (MSW) of 80 kt to 110 kt in less than 20 h, causing more than 400 deaths in Louisiana and Texas due to inadequate preparation for coastal areas (Blake et al., 2011). At nearly the identical landfall location, Hurricane Laura in 2020 underwent a 40 kt rapid intensification in the 24 h prior to landfall (Pasch et al., 2021), bringing heavy damage to southwestern Louisiana (NOAA, 2021). Meanwhile, the deadly reach of hurricanes can also penetrate far inland. For example, Hurricane Michael in 2018 not only underwent rapid intensification, from 100 kt to 140 kt in the 24 h before landfall but maintained tropical storm-force winds even 24 h after landfall, resulting in devastating damage to inland infrastructure (Beven et al., 2019). Hurricane Isaias in 2020 caused widespread damage along the U.S. East Coast due to its slow decay (Latto et al., 2021). Therefore, understanding hurricane MSW change rates before landfall and intensity dissipation rates after landfall are of critical importance for improved hurricane risk mitigation.For hurricanes impacting the continental United States, high ocean heat content along with deep mixed layers in the Gulf are favorable for hurricane intensification prior to landfall (Rappaport et al., 2010), while hurricanes located in the western Atlantic near southeast Florida may intensify when encountering the warm Gulf Stream (Nguyen & Molinari, 2012).

Trends in Western North Pacific Tropical Cyclone Intensity Change Before Landfall

“…TCs forming during June-November (JJASON) are analyzed here, accounting for ∼85% of the annual total number of WNP TCs (Song and Klotzbach, 2019). Similar to Rappaport et al (2010) and Zhu et al (2021), a 24-h track before landfall is identified in this study as when the last record is over land and the previous four 6-h records are all over water. Any 24h tracks with records labeled as extratropical cyclones in the best track data are removed, in order to minimize the influence of extratropical transition on intensity change.…”

Increasing Hurricane Intensification Rate Near the US Atlantic Coast

“…With exposure of the population to hurricanes escalating at a far greater pace than to any other hazard (Iglesias et al., 2020), there are important implications for public health (Parks et al., 2021). Several previous studies have examined changes in various aspects of hurricanes that affect their impacts on land, such as their frequency, intensity, and translation speed (Balaguru et al., 2018; Bender et al., 2010; Bhatia et al., 2019; Elsner et al., 2008; Emanuel, 2005; Klotzbach et al., 2022; Knutson et al., 2020; Knutson et al., 2008; Kossin, 2018; L. Li & Chakraborty, 2020; Murakami et al., 2020; Patricola & Wehner, 2018; Sobel et al., 2016; Vecchi & Soden, 2007a; S. Wang et al., 2020; Webster et al., 2005; Zhu et al., 2021). However, most of these studies were conducted at basin or global scales, and few focused on the nearshore region.…”

The relationship between pre-landfall intensity change and post-landfall weakening of tropical cyclones over China

“…Frontiers in Earth Science frontiersin.org Zhu et al, 2021). Furthermore, it is still unclear how oceanic and atmospheric environmental factors regulate the relationship between the pre-landfall intensity change and the post-landfall weakening of TCs.…”

“…Park et al (2011) analyzed TCs making landfall in Korea and Japan and found a trend of increasing duration after landfall relative to the intensity prior to landfall, and further affect the temporal variation of the TC-induced rainfall in the region. Zhu et al (2021) found that hurricanes undergoing rapid intensification prior to landfall weakened at a slower rate after landfall in the Continental United States and the weakening rate was also weakly and positively correlated with the landfall intensity. They also indicated that the pre-landfall intensification was more common along the Gulf Coast but there was no significant correlation between regions and weakening rate.…”