Climate change and Hurricane Melissa’s historic landfall on Jamaica

Hurricane Melissa was one of the strongest hurricanes in recorded history. Its central pressure and sustained windspeed at peak intensity rank it among the top three Atlantic hurricanes of all time. After a day of rapid intensification over extremely warm seas, Melissa reached this peak intensity just as it made landfall on Jamaica Oct. 28. In addition to the extreme wind speed, storm surge up to four meters and rainfall exceeding half a meter in two days caused catastrophic flooding. The loss of life and structural damage is still being estimated, but by any measure western Jamaica was devastated. 

Climate change affects hurricanes. Hurricane wind speed, precipitation and storm surge are increasing. Other factors, such as annual storm formation and track, have less certain signals, and overall, the climate change impact on hazard (a combination of all factors) has large regional variation.  

In this paper we estimate how much of Melissa’s Jamaica landfall intensity can be attributed to climate change. We find that climate change has made a hurricane of Melissa’s intensity on Jamaica 10 times more likely. Put another way, climate change has increased the intensity of hurricanes with Melissa’s Jamaica landfall odds by 17 km/hr. That 17 km/hr translates to an approximate 20% increase in Melissa’s destructive power.

In this paper we apply the model that S&P Global uses for tropical cyclone risk (Hall et al., 2021) to estimate probabilities and intensities of Melissa-like hurricanes impacting Jamaica. The model simulates many thousands of years of possible hurricanes in specified climate states, using statistical techniques trained on observations. Two environmental variables known to impact Atlantic hurricanes determine the climate state: 1. Seasonally averaged Sea-Surface Temperatures (SST) over the Main Development Region (MDR) of hurricanes in the subtropical North Atlantic, and 2. The state of El Niño/La Niña, a natural irregular climate variation forced in the Pacific that has global weather influence.

Climate change has caused MDR SST to increase but in addition to that increase is considerable year-to-year variability. MDR SST in 2025 was elevated, though not as high as 2024. Meanwhile, El Niño/La Niña was in a mildly negative state (La Niña phase), which is favorable for the formation and development of Atlantic hurricanes.

To assess the impact of climate change on Hurricane Melissa we generate 75,000 years of simulated hurricanes in two combinations of the environmental variables: 

1. El Niño/La Niña and MDR SST in 2025 conditions, representing the current climate.

2. El Niño/La Niña in 2025 conditions, but MDR SST with its climate change component removed. This is the ‘control’ climate — that is, the climate with the same state of natural variability, but without the climate change signal due to human greenhouse gas emissions.

By comparing Melissa-like hurricane hurricanes in 1 to those in 2, we can estimate the impact of climate change on Melissa’s Jamaica landfall.

To remove the climate change signal from MDR SST, we use linear regression to relate the evolution of SST to the global-mean surface air temperature (GSAT). Because it is globally averaged, GSAT has little year-to-year variation. Its upward trend is a response to increased atmospheric greenhouse gases, making it a convenient proxy for climate change. Fig. 1 shows the North Atlantic actual MDR SST evolution from 1948 (red), expressed as a difference from the 1950-2000 mean, and the MDR SST evolution linked to climate change via GSAT (blue). The difference (gray) is the MDR SST evolution in the control climate — that is, a climate with no greenhouse warming. 

It turns out that the 2025 control MDR SST was 0.01 degrees C, close to zero. This is the MDR SST value used in the control hurricane simulations. By contrast, in 2024 SST was significantly higher than its climate change component.

Meanwhile, the El Niño/La Niña state for current and control is a mild La Niña state (-0.5 degrees C for the ‘Niño34’ El Niño/La Niña index), which is favorable for North Atlantic hurricane activity. 

The climate change-linked increase in SST results in many more hurricanes in the simulations reaching Melissa’s intensity level and many more making landfall on Jamaica at that intensity. Fig. 2 shows a small subset of such hurricanes for illustration. First, we extract from the full set of 2025 and control simulated hurricanes those that make landfall on Jamaica. Then, we compute the return period of those landfalling hurricanes in different intensity categories. The return period is a measure of how many years on average between successive landfalls, or equivalently the reciprocal of the annual landfall probability.

The 2025 climate has a lower return period (higher probability) of landfall than the control climate at all intensities (Fig. 3). Equivalently, the 2025 climate has greater intensity at all return periods. For a Melissa-like intensity, the return period decreases from 3,670 to 352 years. That is, climate change has made a landfalling hurricane of Melissa’s intensity or greater 10 times more likely (3,670/352). For a hurricane with a 2025 Melissa-like return period, climate change has increased the intensity 17 km/hr, from 278 to 295 km/hr. (For any Category 5 landfall, intensity of at least 252 km/hr, climate change increases the likelihood by a factor of 3 and the intensity by 34 km/hr.) The damaging power (energy dissipation rate) of wind is proportional to wind speed cubed, and a 278 to 295 km/hr increase translates to an approximate 20% increase in destructive power.

At least two other organizations have estimated how climate change contributed to Melissa’s intensity and likelihood: 

• World Weather Attribution and the Grantham Institute at Imperial College London estimate a factor 5 increased probability for the same intensity and 19 km/hr of increased intensity for the same return period. 

• Climate Central estimates a 16 km/hr increase in Melissa’s intensity due to climate change. Climate Central does not provide an estimate of the change in probability.

Overall, the three estimates of climate change’s impact on Melissa are similar: 16, 17, and 19 km/hr increased intensity and a 5-fold and 10-fold increase in likelihood. The Grantham Institute’s absolute return periods, 8,100 years (‘preindustrial climate’) and 1,700 years (‘current climate’), are considerably longer than our estimates. However, we use the current El Niño/La Niña state, favorable to Atlantic hurricanes, in the 2025 and control climates, which increases the likelihood of intense hurricane landfall. In our analysis, a control state with a neutral El Niño/La Niña would have a Melissa return period of 5,938 years, closer to Grantham’s 8,100 years. 

Given the different methods, the approximate agreement between these three attribution estimates makes a convincing case for the significant impact of climate change on Hurricane Melissa. Quantifying the increasing likelihood and destructive power of strong hurricanes like Melissa in a warming climate can help protect lives, homes and businesses.