Tropical Cyclones and Climate Change Assessment: Part II: Projected Response to Anthropogenic Warming

Abstract

Model projections of tropical cyclone (TC) activity response to anthropogenic warming in climate models are assessed. Observations, theory, and models, with increasing robustness, indicate rising global TC risk for some metrics that are projected to impact multiple regions. A 2°C anthropogenic global warming is projected to impact TC activity as follows. 1) The most confident TC-related projection is that sea level rise accompanying the warming will lead to higher storm inundation levels, assuming all other factors are unchanged. 2) For TC precipitation rates, there is at least medium-to-high confidence in an increase globally, with a median projected increase of 14%, or close to the rate of tropical water vapor increase with warming, at constant relative humidity. 3) For TC intensity, 10 of 11 authors had at least medium-to-high confidence that the global average will increase. The median projected increase in lifetime maximum surface wind speeds is about 5% (range: 1%–10%) in available higher-resolution studies. 4) For the global proportion (as opposed to frequency) of TCs that reach very intense (category 4–5) levels, there is at least medium-to-high confidence in an increase, with a median projected change of +13%. Author opinion was more mixed and confidence levels lower for the following projections: 5) a further poleward expansion of the latitude of maximum TC intensity in the western North Pacific; 6) a decrease of global TC frequency, as projected in most studies; 7) an increase in global very intense TC frequency (category 4–5), seen most prominently in higher-resolution models; and 8) a slowdown in TC translation speed.

It is time to put hurricane preparedness on the radar for individuals living with spinal cord injury

“…Atmospheric scientists have carefully examined the evidence that shows how "climate drivers" such as uncharacteristically warm ocean waters, extending far down below the surface, and warm air temperatures that allow the atmosphere to hold more moisture, are altering how Atlantic hurricanes behave [4,5]. Collectively, these storms are becoming stronger, in terms of higher peak wind speeds and rapid intensification, and wetter, in terms of increased precipitation rates and rainfall totals [4][5][6]. Moreover, the forward motion "translational" speed of some storms slows to near standstill above populated areas, adding to the devastation and trauma experienced by the affected communities [6,7].…”

Lagrangian Analysis of Tropical Cyclone Genesis Simulated by General Circulation Models Compared with Observations

“…A general circulation model (GCM) that can simulate the observed properties of TCs (e.g., spatial distribution, annual cycle, and strength) reasonably well, if any, could supplement the weakness of the previous observational and modeling studies. In particular, a GCM can be used to study changes of TC activity in a warm climate induced by the increased concentration of carbon dioxide (e.g., Knutson et al 2019).…”

A New Method to Construct a Horizontal Resolution‐Dependent Wind Speed Adjustment Factor for Tropical Cyclones in Global Climate Model Simulations

“…How tropical cyclone (TC) activity—such as frequency, intensity distribution, and tracks—will change in a warming climate has been the subject of numerous studies in the past (e.g., Bindoff et al, 2013; Knutson et al, 2010; Knutson et al, 2019; Walsh et al, 2016). Global climate models (GCMs) have been an indispensable tool in this endeavor, especially after continued improvements in computational power and numerical methods have made it more attainable to perform long‐term GCM simulations of TCs with horizontal grid spacing of half degree or less (e.g., Camargo & Wing, 2016).…”