THE CLIMATE NOTEBOOK
Hurricanes and climate change
Storm counts and storm intensity tell different stories. Explore the historical archive, then put what you see alongside the climate evidence.
What does the research say?
The IPCC’s 2021 assessment finds that the global proportion of major (Category 3–5) tropical cyclone intensity observations likely increased over the preceding four decades. It also assesses low confidence in long-term trends in the frequency of all-category tropical cyclones. IPCC AR6, Chapter 11.
Warming is expected to increase average tropical cyclone intensity and rainfall rates. Total global cyclone numbers are generally projected to decrease or change little, while the proportion of very intense storms rises. Sea-level rise also increases the coastal flooding associated with a storm, other things being equal. Research overview by Tom Knutson, NOAA GFDL.
“More storms” and “stronger storms” are not interchangeable. A larger major-storm share can occur even if the total number falls.
Explore counts and intensity since 1980
These charts summarize this site’s IBTrACS records. They measure unique storms and each storm’s peak tropical-stage wind. They do not reproduce the IPCC assessment’s metric of intensity observations, and cannot establish how much of a change was caused by warming.
Global · 1980–2025 · 3,714 storms reached 34 knots across charted years. Unfinalized years shown as gaps: 2024, 2025.
How many storms?
Unique tropical cyclones reaching at least 34 knots in each formation year.
Annual count 5-year average
How many become major?
Percentage of hurricane-strength cyclones (≥64 knots) reaching major intensity (≥96 knots).
Annual share 5-year pooled share
Both charts use US-agency one-minute winds during tropical stages only. 545 records have no usable tropical-stage US wind; 80 provisional or unfinished records are excluded. Wind coverage and observation methods vary through time. These are archive summaries, not an attribution study.
View annual counts, intensity, and data coverage
| Year | Records | ≥34 kt | ≥64 kt | ≥96 kt | Major share | No US wind | Excluded |
|---|---|---|---|---|---|---|---|
| 1980 | 107 | 71 | 43 | 19 | 44.2% | 26 | 0 |
| 1981 | 108 | 78 | 44 | 15 | 34.1% | 18 | 0 |
| 1982 | 116 | 80 | 46 | 21 | 45.7% | 31 | 0 |
| 1983 | 99 | 79 | 42 | 21 | 50.0% | 14 | 0 |
| 1984 | 115 | 91 | 47 | 20 | 42.6% | 15 | 0 |
| 1985 | 121 | 95 | 51 | 24 | 47.1% | 20 | 0 |
| 1986 | 106 | 86 | 46 | 16 | 34.8% | 13 | 0 |
| 1987 | 103 | 81 | 38 | 18 | 47.4% | 10 | 0 |
| 1988 | 106 | 75 | 39 | 18 | 46.2% | 16 | 0 |
| 1989 | 128 | 91 | 56 | 25 | 44.6% | 17 | 0 |
| 1990 | 114 | 86 | 55 | 19 | 34.5% | 17 | 0 |
| 1991 | 98 | 74 | 45 | 24 | 53.3% | 14 | 0 |
| 1992 | 114 | 90 | 56 | 31 | 55.4% | 17 | 0 |
| 1993 | 98 | 76 | 46 | 25 | 54.3% | 13 | 0 |
| 1994 | 113 | 90 | 50 | 29 | 58.0% | 8 | 0 |
| 1995 | 94 | 72 | 47 | 24 | 51.1% | 13 | 0 |
| 1996 | 116 | 97 | 57 | 26 | 45.6% | 11 | 0 |
| 1997 | 106 | 91 | 56 | 27 | 48.2% | 9 | 0 |
| 1998 | 106 | 84 | 49 | 20 | 40.8% | 14 | 0 |
| 1999 | 103 | 72 | 38 | 20 | 52.6% | 16 | 0 |
| 2000 | 110 | 88 | 47 | 22 | 46.8% | 8 | 0 |
| 2001 | 108 | 88 | 48 | 22 | 45.8% | 10 | 0 |
| 2002 | 97 | 79 | 41 | 27 | 65.9% | 4 | 0 |
| 2003 | 104 | 83 | 49 | 23 | 46.9% | 9 | 0 |
| 2004 | 103 | 84 | 50 | 31 | 62.0% | 10 | 0 |
| 2005 | 115 | 93 | 50 | 26 | 52.0% | 16 | 0 |
| 2006 | 101 | 81 | 43 | 27 | 62.8% | 9 | 0 |
| 2007 | 94 | 78 | 43 | 22 | 51.2% | 3 | 0 |
| 2008 | 99 | 88 | 40 | 24 | 60.0% | 5 | 0 |
| 2009 | 100 | 83 | 38 | 21 | 55.3% | 7 | 0 |
| 2010 | 88 | 66 | 37 | 17 | 45.9% | 11 | 0 |
| 2011 | 95 | 75 | 39 | 21 | 53.8% | 8 | 0 |
| 2012 | 94 | 87 | 48 | 24 | 50.0% | 3 | 0 |
| 2013 | 102 | 87 | 44 | 22 | 50.0% | 7 | 0 |
| 2014 | 89 | 76 | 46 | 26 | 56.5% | 7 | 0 |
| 2015 | 111 | 92 | 53 | 38 | 71.7% | 12 | 0 |
| 2016 | 97 | 84 | 48 | 26 | 54.2% | 7 | 0 |
| 2017 | 108 | 85 | 43 | 20 | 46.5% | 13 | 0 |
| 2018 | 118 | 102 | 58 | 32 | 55.2% | 7 | 0 |
| 2019 | 109 | 93 | 54 | 34 | 63.0% | 11 | 0 |
| 2020 | 121 | 104 | 46 | 24 | 52.2% | 9 | 0 |
| 2021 | 106 | 93 | 38 | 16 | 42.1% | 9 | 0 |
| 2022 | 112 | 90 | 42 | 17 | 40.5% | 16 | 0 |
| 2023 | 90 | 76 | 47 | 30 | 63.8% | 7 | 0 |
| 2024* | 104 | 80 | 41 | 21 | 51.2% | 11 | 7 |
| 2025* | 119 | 32 | 16 | 9 | 56.3% | 14 | 73 |
How these charts are calculated
We count each unique IBTrACS storm ID once, assigning it to the calendar year of its first recorded point and its archive basin. A cross-basin storm is counted in that assigned basin only. Southern Hemisphere calendar-year counts therefore differ from official season totals.
Only US-agency one-minute winds at tropical-stage observations (IBTrACS NATURE = TS) are used. The thresholds are 34 knots for tropical-storm strength, 64 knots for hurricane strength, and 96 knots for major intensity. WMO fallback winds are not mixed in. These categories are used consistently for the chart, regardless of a storm’s regional name.
The major share divides storms reaching 96 knots by storms reaching 64 knots, not by all tropical storms. A year with no hurricane-strength storms has no defined share, rather than a zero-percent share. The gold line pools five years of major and hurricane-strength counts for the share; it averages five annual counts for the frequency chart.
The data window ends at 2025, the year before the latest observation’s calendar year. Provisional records and tracks extending beyond that cutoff are excluded. Any year with these exclusions is shown as a gap in both charts and five-year lines, so an unfinished archive does not create a false decline. Its partial counts remain labeled in the table and downloads.
Records with no usable tropical-stage US wind do not enter intensity counts; the table reports their number. Records with only some wind observations can still underestimate peak intensity.
Why start in 1980?
The start focuses the view on the modern satellite era, but it does not make the archive uniform. Instruments, estimation methods, and agency coverage still differ over time and between basins. The raw archive cannot separate those changes from natural variability or human influence.
What “severity” leaves out
These charts measure wind intensity. They do not measure deaths, economic losses, rainfall, or flood depth. Interpreting storm impacts requires additional observations and context; a wind-only chart cannot stand in for all of them.
Source retrieved 2026-09-10. Download all chart data as JSON or read the archive methodology. For further interpretation, use the IPCC assessment and GFDL research overview.