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International Best Track Archive for Climate Stewardship (IBTrACS)

The International Best Track Archive for Climate Stewardship (IBTrACS) project is the most complete global collection of tropical cyclones available. It merges recent and historical tropical cyclone data from multiple agencies to create a unified, publicly available, best-track dataset that improves inter-agency comparisons. IBTrACS was developed collaboratively with all the World Meteorological Organization (WMO) Regional Specialized Meteorological Centres, as well as other organizations and individuals from around the world.  

IBTrACS Version 4

Documentation

Technical Documentation
Caveats, usage information, and other details about how to use and apply IBTrACS data.

V04 Column Documentation
Descriptions of each CSV and shapefile data column.

Storm ID: 
Information on IBTrACS storm identifier (SID).

Dataset Identifiers

Hurricane Isabel (9/14/2003)

Citation

New users should document their data usage and provide feedback by completing IBTrACS voluntary User Registration. This information helps the IBTrACS team justify continued updates and support.

Please use both the BAMS paper and dataset citations when referencing IBTrACS in a written work that has a bibliography:

  • Knapp, K. R., M. C. Kruk, D. H. Levinson, H. J. Diamond, and C. J. Neumann, 2010: The International Best Track Archive for Climate Stewardship (IBTrACS): Unifying tropical cyclone best track data. Bulletin of the American Meteorological Society, 91, 363-376. doi:10.1175/2009BAMS2755.1
  • Knapp, K. R., H. J. Diamond, J. P. Kossin, M. C. Kruk, C. J. Schreck, 2018: International Best Track Archive for Climate Stewardship (IBTrACS) Project, Version 4. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.25921/82ty-9e16 [access date].

When the written work does not have a bibliography, please use:

  • NOAA's International Best Track Archive for Climate Stewardship (IBTrACS) data, accessed on [Access Date]

Update Schedule

IBTrACS v04 is updated twice a week (usually on Monday and Friday), and could be updated more frequently to address specific needs and use cases. Fill out the voluntary User Registration Form to let us know if more frequent updates would help your project or research.

Access Methods

NetCDF

NetCDF is a self describing, mostly CF compliant format that uses global and variable attributes. Data are stored using the netCDF4 library.

netCDF Data

Comma Separated Values (CSV)

Missing data are stored as blank cells to decrease file sizes (other netCDF and shapefiles use -9999.0 for missing data).

Shapefiles

Files are available as point and line shapefiles. Zip files are provided to simplify download. These include the usual shapefile parts (prj, shx, shp, and dbf files).

File metadata (xml files) are not currently available. The CSV column description file can be referenced for the definitions of each variable.

Shapefile Data

Tropical cyclone track data is available in several subsets, including:

ALL: 
All storms available in the IBTrACS record

since1980:
The modern era of satellite observations

last3years: 
3 most recent years of data

active: 
storms active in the last 7 days

by basin:
  • NI - North Indian
  • SI - South Indian
  • WP - Western Pacific
  • SP - Southern Pacific
  • EP - Eastern Pacific
  • NA - North Atlantic

Release Information: v04r00

The first iteration of IBTrACS version 04 was released in March of 2019. It is updated weekly.

New Features (Improvements from v03)

  • Best track data are updated daily, and contain provisional tracks of recent storms.
  • Data are available in three inter-consistent (identical parameters, file structure, etc) formats (netCDF, CSV, shapefile). 
  • More parameters are available from best track data providers. 
  • Basin Assignment: Systems that occur within a basin are included in that basin file (in version 3, the storm was only included in its basin of origin)
  • Storm translation speed and direction and other derived parameters requested by users are available in version v.

Known Issues

Check the IBTrACS News Forum for status updates. 

Some early (pre-1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so the same storm is tracked by the following identifiers: ds824, td9636, and reunion. This storm is broken into different tracks because of temporal differences in the storm data.

v03r10

The last IBTrACS version 03 release. It includes storm data through 2016. The following is a summary of changes for v03r10.

Release date: 20 Sep 2017

New Features
  • Best track data through 2016
  • IBTrACS applied the new HKO categories to all HKO data to provide consistent storm categories.
Bug Fixes
  • No major changes from v03r09.
Known Issues
  • New datasets can cause new agency ordering in CSV and netCDF files
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r09

The latest IBTrACS version includes storm data through 2015. The following is a summary of changes for v03r09.

Release date: 30 Sep 2016

New Features
  • Best track data through 2015
Bug Fixes
  • No major changes from v03r08.
Known Issues
  • New datasets can cause new agency ordering in CSV and netCDF files
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r08

Release date: 15 Jan 2016

New Features
  • Best track data through 2014
  • Two small bug fixes from v03r07
Bug Fixes
  • Line shapefiles often had errant start and end lines
  • In v03r07, there were five errant systems (INVESTs) in the North Atlantic that were not classified as tropical storms by NHC in HURDAT data. These were removed in v03r08.
Known Issues
  • New datasets can cause new agency ordering in CSV and netCDF files
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r07

Release date: 22 Oct 2015

New Features
  • Best track data through 2014
  • New 19th Century data for the North Atlantic from Mike Chenoweth This has a large effect on North Atlantic systems in the 19th century.
  • New subbasins - We have finally implemented Gulf of Mexico and Caribbean Sea sub basins of the Atlantic. We used the definitions from the IHO (International Hydrographic Organization), using data from Marine Regions website.
Bug Fixes
  • There was a small bug that ocurred when a storm had few (1 or 2) points in its track. This has a small effect on a few storms
Known Issues
  • Line shapefiles often had errant start and end lines
  • In v03r07, there were five errant systems (INVESTs) in the North Atlantic that were not classified as tropical storms by NHC in HURDAT data. These were removed in v03r08.
  • New datasets can cause new agency ordering in CSV and netCDF files
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r06

Release date: 2 Sep 2014

New Features
  • Best track data through 2013
  • Landfall Variables
    • New variables in netCDF provide information on storm location with respect to land. The new variable dist2land provides information on the current distance to land. The new variable landfall provides the minimum distance to land between the current time and the next reporting time. Landfalling storms would at least one occurrences of a dist2land value > 0 but landfall = 0
  • Improved North Atlantic/Eastern Pacific Basin delineation
Bug Fixes
  • ATCF data from JTWC and NHC was being read in incorrectly. This caused a problem in many storm properties (wind radii, storm type, etc.) in previous IBTrACS versions.
  • A HURDAT2 reading error was corrected (error affected only v03r05 wind radii since it was the first year with HURDAT2 data)
  • Corrected an error in Wellington data for 2011 Wilma (problem with longitude positions near dateline)
Known Issues
  • New datasets can cause new agency ordering in CSV and netCDF files
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r05

Release date: 4 Nov 2013

New Features
  • Best track data through 2012
  • Data includes new data format from HURDAT which includes a) observations at non-synoptic times (e.g., near landfall or maximum intensity) and b) other variables (e.g., wind radii)
Bug Fixes
  • Data
    • Fixed assignment of dates to some tracks from the 1800s whose starting dates were approximate.
    • Modified WMO agency identification to allow BoM to backup TCWCs Nadi and Wellington if either were missing but BoM was present. This fixed REWA (1993) where WMO track had gaps due to nadi not reporting the storm.
  • Known Bugs
    • New dataset causes new agency ordering in CSV and netCDF files
    • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the stormdata).

v03r04

Release date: 1 Oct 2012

New Features
  • Best track data through 2011
  • New dataset: Typhoon Analogs - Data for historical typhoons (1945-1976) includes numerous new parameters, recently uncovered at NCDC
Bug Fixes
  • Data
    • Removed non-developing storms that slipped in through ATCF B decks with numbers more than 49 (e.g., bal502007.dat)
    • Fixed basin discrepancy between IBTrACS-All and IBTrACS-WMO occurring for some storms
  • Shapefiles
    • Fixed ArcGIS ingest error caused by column headers having spaces.

v03r03

Release date: 19 July 2011

New Features
  • New data through 2010 for all agencies
  • v03r03/ibtracs/*.nc files - New variable - wind_avg_period
  • v03r03/all/shp - shapefiles - Support of shapefiles is a new development and should be considered as a test phase as this is our first dataset release with access to shapefiles directly produced by the IBTrACS software.
    Using the IDL, shape files are created. Files are available for: individual storms, concatenated by year, concatenated by basin, or a file with everything.
  • v03r03/all/netCDF files
    • New attribute: source
    • New variables: lat_for_mapping, lon_for_mapping and basin
    • Added variable attribute "_FillValue"
  • v03r03/all/CSV files - New column/variables: lat_for_mapping, lon_for_mapping, track_type, and current basin
  • v03r03/all/CSV/basin files - Columns with all missing data (no valid reports) have been removed
  • v03r03/ibtracs/*.nc files and WMO files: netCDF, WMO, CSV, cXML - N. Atlantic, E. Pac. and C. Pac WMO source changed from HURDAT/CPHC to ATCF
Bug Fixes
  • Data
    • Some time parameters were stored in netCDF files as floats instead of doubles. One place this impacted were in the ISO times in the CSV files. The result was wrong times (due to truncation of the floats). This is now fixed in v03r03.
    • Corrected spuriously low winds in TD9636 data (1885 and 1897 and 1945).
    • Corrected a wind speed for ATCF bal191974.dat (2 --> 25)
    • Corrected WMO tracks of spurs - Spurs containing WMO data inadvertently contained the entire WMO track instead of the just the portion that was a spur.
    • Corrected a wind speed for Wellington 1974 ALICE: 6 --> 60
  • CSV files
    • Storm names no longer have commas.
    • Corrected storm ordering.
  • HURDAT_format files
    • Corrected storm nature assignments.
    • For NHC storms, the XING, SSS and maximum storm intensity now derive directly from the original HURDAT file. For other basins, maximum storm type is now assigned based on maximum intensity as a tropical cyclone
  • WMO NetCDF file - source data was inadvertantly assigned only for the first observation. Source data is now (v03r03) assigned for each storm report.
Known Bugs
  • Some early (pre 1950) storms were not correctly matched, so the number of storms in the record is artificially high. For example, SIO storms in 1901 are not matched, so ds824/td9636/reunion all track one storm, but is not identified as the same storm, so 3 separate tracks are created (due to temporal differences in the storm data).

v03r02

The only change between v03r01 and v03r02 is that the CMA/Shanghhai Typhoon Institute data was updated based on their September update.

Release date: 17 Sep 2010

v03r01

There are numerous changes and improvements from v02r01 to v03r01. A summary is below.

Release date: 1 Sep 2010

Best track Period of Records for IBTrACS
  • 1906-2006 - Australian TCWCs (BoM)
  • 1848-2009 - RSMC La Reunion (MFLR)
  • 1851-2009 - RSMC Miami (HURDAT & ATCF)
  • 1990-2009 - RSMC New Delhi (IMD)
  • 1951-2009 - RSMC Tokyo (JMA)
  • 1966-2008 - RSMC Honolulu (MS Excel file and ATCF B Decks)(CPHC)
  • 1992-2009 - RSMC Nadi (FMS)
  • 1968-2009 - TCWC Wellington (NZMS)
  • 1949-2009 - CMA/STI
  • 1945-2009 - JTWC
  • 1961-2009 - HKO
  • 1960-2007 - Neumann
  • 1842-1989 - NCDC Data Set 9636
New Data Sources
  • 2006-2009 - BoM Operational data (best track data not yet available)
  • 2009-2009 - CPHC Operational data (best track data not yet available)
  • 1877-1980 - UCAR ds824.1 - Global Tropical Cyclone "Best Track" Position and Intensity Data (not using data after 1980). Warning: ds824 provides wind speed when only the storm category was known (TD, TS or HR) and lists them as 25E or 35E or 65E. IBTrACS does not yet denote wind quality in many formats. Use wind data from ds824 with caution until a future IBTrACS release accurately denotes the wind quality.
Changes from v02r01 that affect cyclone data
  • Intensity percentiles are now provided. The percentiles are calculated per agency and per basin. Percentiles are compiled based on a limited period record (1970-2009).
  • Data are now provided in IBTrACS as it is provided to us. We no longer convert all observations to a 10-min wind speed.
Deprecated
  • IBTrACS-ASCII format - This format is no longer produced or supported. Users of ibtracs_ascii should now use the CSV or netCDF files.
Known Bugs
  • Some of the earliest storms in the South Indian Ocean (before 1890) have differing positions between La Reunion and DSI-9636.

Due to the amount of changes from version 2, the number was incremented to Version 3.

As this is the first release of version 2, it is named Release 1.

v02r01

There are numerous changes and improvements from v01cor-r01 to v02r01. A summary is below.

Release date: 24 Jul 2009

Updates from best track data sources through calendar year 2008:
  • RSMC Miami (HURDAT) for North Atlantic and Eastern Pacific
  • RSMC Tokyo (JMA) Western Pacific
  • RSMC New Delhi (IMD) Northern Indian
  • CMA/STI - Western Pacific
  • JTWC - Western Pacific, Northern Indian, Southern Hemisphere
New Data Sources
  • NOAA ATCF B Deck for North Atlantic and Eastern & Central Pacific
  • NCDC DSI-9636 - Global Consolidated Tropical Cyclone Data
Changes from v01cor-r01 that affect cyclone data
  • Correction to pres_minimum and pres_maximum
  • New treatment of Neumann data
  • New adjustment for CMA wind reports
  • JTWC storm type now incorporated into IBTrACS
  • Adjustment to the method for classiying storm trackss as spurs.
  • Bug fix - Correction on how BoM data was read in for storms reported in more than one type of unit
Changes from v01cor-r01 that do not affect cyclone data
  • Original reports of position and intensity from each agency are now available in some formats:
    • ibtracs - Official IBTrACS Dataset netCDF format
    • ibtracs_net - IBTrACS data for all cyclones in one large file
    • ibtracs_csv - IBTrACS data in a comma separated file
  • ibtracs_csv - now has two more header lines which provide column names and units
Known Bugs

Some of the earliest storms in the South Indian Ocean (before 1890) have differing positions between La Reunion and DSI-9636.

Due to the amount of changes from version 1, the number was incremented to Version 2.

As this is the first release of version 2, it is named Release 1.

v01cor-r01

All data are identical to v01r01, except for the corrections listed below. Check this area frequently as it may be updated without notice

Release date: 12/23/2008

Corrections that affect storm data
  • ibtracs_tape: Winds are now 10-min winds.
Corrections that do not affect storm data
  • ibtracs_net: Made CF-1.0 compliant
    • Corrected wind speed units: "kn" → "kt" and "knots" → "kt"
    • Corrected scale_factor for variables: lat, lon, pres and wind
Known Bugs
  • Minimum and maximum pressure values are reversed in IBTrACS v01r01 and v01cor-r01. That is, the minimum pressure value from the available centers is reported as the maximum and vice versa. This will be corrected in a future release of IBTrACS.
  • Error in BoM intensities - For some storms reported by BoM, intensities were incorrectly ingested into IBTrACS. This only affects cyclones where BoM changed the wind speed units during a storm's lifetime. In such cases, speeds were incorrectly handled (either by not converting m/s to kt or by converting kt to m/s). This bug is present v01r01, too, and is corrected in v02r01.

v01r01

Release Date 12/15/2008

Version 1.0, Release 01

Bugs
  • ibtracs_tape: Wind speeds in ibtracs_tape files (i.e., HURDAT format) were inadvertantly provided as 1-minute winds. Winds should be corrected back to 10-minute by multiplying wind speeds by 0.88.
  • ibtracs_net: files are not CF-compliant
  • These bugs are corrected in v01cor-r01 (see above)

BETA00x

  • Test versions (BETA00x) of the data set were available but are superceded by the release of IBTrACS version 1.

Browse IBTrACS Data

IBTrACS Browser (Hosted by UNC Asheville)

View storm imagery (based on HURSAT), tracks, intensities and raw data.

IBTrACS Browser

CSC Historic Hurricane Track Mapper

Use this interactive map tool to search historic hurricane data (from IBTrACS and other datasets) by location, name, year, zip code, or basin. 

 Hurricane Track Mapper

Principles

Global

IBTrACS merges Tropical Cyclone (TC) storm track datasets from agencies around the world to create a global, best track TC database.

Open

The methods used to merge and maintain the data will be public, and all data quality revisions and additions will be recorded and open for review. Information about the integrity or quality of a storm track will also be available to the agencies that provide track data.

Provenance

All changes to data will be recorded, and each version of the data will be maintained. Data provenance will be recorded to preserve traceability, and to make it easy to identify data sources. The reasoning behind changes and algorithms that merge and adjust the datasets will be recorded so that the data can be well understood for years to come.

Ongoing

The dataset production will be ongoing and updated annually (in the boreal summer following the completion of the Northern Hemisphere TC season).

Accessibility

NCEI will maintain the official archive of this product in one format, but will provide the dataset in formats that are already used by the TC community.

Third IBTrACS Workshop

Group photo from Third IBTrACS Workshop

Purpose

This workshop was an opportunity for the IBTrACS Team to interact with technical and management staff from Regional Specialized Meteorological Centers and Tropical Cyclone Warning Centers around the world. The goal of these discussions were to improve the quality and utility of the IBTrACS dataset, discuss the production of best track data and the related data uncertainty, and develop an approach to deriving (as originally laid out by IWTC-VI) a "singular, uniform global best track dataset."

More Information

Best Track Data Sources in IBTrACS

Data in IBTrACS fall into one of three categories: static (no longer updated), annual updates, and daily updates.

Static Best Track Sources

  • Charlie Neumann Southern Hemisphere Data
  • Michael Chenoweth North Atlantic 19th Century Reanalysis
  • TD9636: Global, consolidated tropical cyclone data that was jointly produced by the National Climatic Data Center (NCDC) and the Navy in the 1980s.
  • TD9635: A historical set of reports on West Pacific systems that includes unique variables. 
  • dsi824: The data are updated regularly by the National Center for Atmospheric Research (NCAR),  but their source for recent years is the Joint Typhoon Warning Center (JTWC). 

Annually-Updated Best Track Sources

Daily-Updated Provisional Track Data Sources

  • TC Vitals
  • NCAR Tropical Cyclone Guidance Project
  • NHC provisional data

Tropical Cyclone Climatology

The following is a summary of annual or monthly counts based on IBTrACS. When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014:
The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review, 142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

The Tropical Cyclone Climatology was constructed using two different approaches based on reports and data from the following organizations:

World Meteorlogical Organization (WMO)

Climatology based on reports from the WMO official forecast centers (referred to as RSMCs and TCWCs).

National Hurricane Center (NHC) and Joint Typhoon Warning Center (JTWC)

Climatology based on the combination of the NHC best track data for the North Atlantic and Eastern Pacific the JTWC for other basins.


 
Time series of the number of storms for WMO and NHC+JTWC Climatologies

WMO Annual Tropical Cyclone Numbers 

Based on tables 3 and 4 and figure 4 from Schreck et al. (2014)

Number of storms with winds ≥ 35 knots (e.g., tropical storms)

Annual average mean number of storms with maximum sustained winds of at least 35 knots for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic198112.14.981215
East Pacific198116.54.61416.520
West Pacific198125.04.2222528
North Indian19813.91.2344.25
South Indian1981/828.42.47.75810
Australian1984/859.13.17911
South Pacific1980/816.83.9469
Northern Hemisphere198157.56.2525561
Southern Hemisphere1980/8124.34.72022.526
Global198181.87.87479.585

Number of storms with winds ≥ 64 knots (e.g., hurricanes)

Annual average mean number of storms with maximum sustained winds of at least 64 knots for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic19816.43.146.58
East Pacific19818.93.178.511
West Pacific198115.34.11316.518
North Indian19811.40.9112
South Indian1981/824.72.3356
Australian1984/855.42.5457
South Pacific1980/814.02.8146
Northern Hemisphere198132.04.9283235
Southern Hemisphere1980/8114.13.6121316
Global198146.16.0404649

Number of storms with winds ≥ 96 knots (e.g., major hurricanes)

Annual average mean number of storms with maximum sustained winds of at least 96 knots for the period from the initial year through 2010

Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic19812.71.9124
East Pacific19814.32.6246
West Pacific19817.53.067.59
North Indian19810.60.7011
South Indian1981/822.41.8124
Australian1984/852.61.6124
South Pacific1980/811.61.7012
Northern Hemisphere198115.13.4131417
Southern Hemisphere1980/816.62.746.58
Global198121.74.6182123

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACSMonthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

NHC and JTWC Annual Tropical Cyclone Numbers

Based on tables 3 and 4 and Figure 4 from Schreck et al. (2014)

Number of storms with winds ≥ 35 knots (e.g., tropical storms)

Annual average mean number of storms with maximum sustained winds of at least 35 knots for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic198112.14.981215
East Pacific198116.54.61416.520
West Pacific198125.74.2232529
North Indian19814.91.9456
South Indian1980/819.01.98910
Australian1980/8110.44.0710.513
South Pacific1980/816.33.545.58
Northern Hemisphere198159.26.6555863
Southern Hemisphere1980/8125.74.3232528
Global198184.97.6798590

Number of storms with winds ≥ 64 knots (e.g., hurricanes)

Annual average mean number of storms with maximum sustained winds of at least 64 knots for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic19816.43.146.58
East Pacific19818.93.178.511
West Pacific198116.63.8141720
North Indian19811.51.3112
South Indian1980/815.42.145.57
Australian1980/814.41.8345
South Pacific1980/811.91.7235
Northern Hemisphere198133.45.2293337
Southern Hemisphere1980/8113.53.1111315
Global198146.96.2424751

Number of storms with winds ≥ 96 knots (e.g., major hurricanes)

Annual average mean number of storms with maximum sustained winds of at least 96 knots for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic19812.71.9124
East Pacific19814.32.6246
West Pacific19818.82.67911
North Indian19810.70.7011
South Indian1981/822.91.6234
Australian1984/852.01.411.53
South Pacific1980/811.91.7113
Northern Hemisphere198116.53.21416.519
Southern Hemisphere1980/816.82.6578
Global198123.34.3212427

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

WMO Accumulated Cyclone Energy

Based on tables 5 and 6 and figure 7 from Schreck et al.(2014)

Total annual average ACE (Accumulated Cyclone Energy) [10-4 kt2] for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic1981105664192166
East Pacific19811326190120178
West Pacific198127693219266361
North Indian198112691116
South Indian1981/8274364673100
Australian1984/857733508199
South Pacific1980/815943225185
Northern Hemisphere1981525107443508575
Southern Hemisphere1980/8121058150210246
Global1981735142616694808

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS Monthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

NHC and JTWC Accumulated Cyclone Energy

Based on tables 5 and 6 and figure 7 from Schreck et al. (2014)

Total annual average ACE (Accumulated Cyclone Energy) [10-4 kt2] for the period from the initial year through 2010
Percentiles
BasinInitial YearMeanStd. Dev.25th50th75th
North Atlantic1981105664192166
East Pacific19811326190120178
West Pacific1981305109225306356
North Indian19811911131625
South Indian1980/8192406989118
Australian1980/816226485976
South Pacific1980/815039184068
Northern Hemisphere1981561128463542645
Southern Hemisphere1980/8120455162193233
Global1981765165645717853

When using these numbers in any publication, please cite: Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS Monthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

WMO Monthly Average Tropical Cyclone Numbers

Based on figure 9 from Schreck et al. (2014)

Average number of storms per month for the period from the initial year through 2010
 Month
BasinInitial YearJanFebMarAprMayJunJulAugSepOctNovDec
North Atlantic19810.00.00.00.10.10.61.13.34.02.00.70.2
East Pacific19810.00.00.00.00.71.93.64.23.62.10.30.1
West Pacific19810.30.10.30.61.11.73.55.64.73.62.31.1
North Indian19810.10.10.10.20.70.40.00.00.20.81.00.4
South Indian1981/822.02.21.40.70.30.10.00.00.10.10.61.0
Australian1984/852.01.82.01.40.30.00.00.00.00.10.41.2
South Pacific1980/811.51.81.40.60.20.10.00.00.00.10.40.7
Northern Hemisphere19810.40.20.40.92.54.78.313.112.58.44.31.8
Southern Hemisphere1980/815.55.84.72.60.80.10.00.00.10.31.32.9
Global19815.96.05.13.63.34.88.313.112.68.85.64.7

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review, 142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

NHC and JTWC Monthly Average Tropical Cyclone Numbers

Based on figure 9 from Schreck et al. (2014)

Average number of storms per month for the period from the initial year through 2010
 Month
BasinInitial YearJanFebMarAprMayJunJulAugSepOctNovDec
North Atlantic19810.00.00.00.10.10.61.13.34.02.00.70.2
East Pacific19810.00.00.00.00.71.93.64.23.62.10.30.1
West Pacific19810.40.10.40.61.11.73.65.54.83.72.41.3
North Indian19810.10.10.00.20.80.50.10.00.31.01.20.5
South Indian1981/822.12.11.40.60.20.10.10.10.20.40.71.0
Australian1984/852.22.32.01.50.30.00.10.00.00.10.51.2
South Pacific1980/811.41.61.30.50.10.10.00.00.00.20.30.8
Northern Hemisphere19810.60.20.50.92.74.78.413.112.78.84.72.1
Southern Hemisphere1980/815.76.04.82.70.70.10.20.10.30.61.53.1
Global19816.36.25.23.53.44.98.613.112.99.46.25.1

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review, 142, 3881-3899. doi:10.1175/MWR-D-14-00021.1 

WMO Monthly Accumulated Cyclone Energy Values

Based on Figure 10 from Schreck et al. (2014)

Average number of storms per month for the period from the initial year through 2010
Month
BasinInitial YearJanFebMarAprMayJunJulAugSepOctNovDec
North Atlantic19810.20.00.00.10.11.26.124.851.414.55.81.4
East Pacific19810.20.30.00.02.711.027.833.835.818.31.50.3
West Pacific19812.30.32.86.010.713.431.653.861.050.429.114.5
North Indian19810.10.00.01.33.71.50.00.00.21.33.11.2
South Indian1981/8216.019.216.58.71.40.10.00.00.10.45.76.3
Australian1984/8512.013.223.113.71.90.00.00.00.10.12.111.0
South Pacific1980/8113.815.415.13.90.90.60.00.00.00.52.17.0
Northern Hemisphere19812.70.52.87.517.127,165.6112.3148.484.439.517.4
Southern Hemisphere1980/8141.747.854.726.34.10.70.00.00.21.09.824.3
Global198144.448.357.533.721.227.865.6112.3148.685.449.441.7

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

NHC and JTWC Monthly Accumulated Cyclone Energy Values 

Based on Figure 10 from Schreck et al. (2014)

Average number of storms per month for the period from the initial year through 2010
Month
BasinInitial YearJanFebMarAprMayJunJulAugSepOctNovDec
North Atlantic19810.20.00.00.10.11.26.124.851.414.55.81.4
East Pacific19810.20.30.00.02.711.027.833.835.818.31.50.3
West Pacific19812.50.33.17.912.114.333.756.965.056.735.416.6
North Indian19810.20.10.01.34.22.30.00.00.32.36.22.0
South Indian1981/8220.022.619.011.31.30.10.10.10.41.27.88.5
Australian1984/8510.010.919.110.71.20.00.00.00.10.21.78.2
South Pacific1980/8112.312.812.13.00.30.60.00.00.00.52.26.4
Northern Hemisphere19813.00.63.29.319.128.867.7115.5152.491.848.920.3
Southern Hemisphere1980/8142.446.350.225.02.80.70.20.10.41.911.723.0
Global198145.446.953.434.321.829.567.8115.6152.993.760.643.4

When using these numbers in any publication, please cite:

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS, Monthly Weather Review142, 3881-3899. doi:10.1175/MWR-D-14-00021.1

Please note the following caveats when using information from these tables

Initial dates vary: Data from some agencies are not available for all 30 years of the climatology.

Counts based solely on wind: The climatologies are based solely on wind speed. Storms without wind speeds were not included in the climatology. Wind speed data is available for most storms from 1980–2010.

Wind speed homogeneities: Wind speed averaging periods vary between agencies, which affects the WMO inter-basin count values. In this climatology, we attempted to reduce these differences by converting to 1-min winds.

Counting monthly storms: Storms are only for the month they start in. However, ACE values are only calculated for the portion of the storm during that month.

Counting storms in basins: A storm is only counted in a basin if it starts in that basin.

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Basin Map

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Related Publications

Schreck III, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS. Monthly Weather Review, 142, 3881-3899. doi:10.1175/MWR-D-14-00021.1


Knapp, K. R., J. A. Knaff, C. R. Sampson, G. M. Riggio, and A. D. Schnapp, 2013: A pressure-based analysis of the historical western North Pacific tropical cyclone intensity record. Monthly Weather Review, 141, 2611-2631. doi:10.1175/MWR-D-12-00323.1.


Diamond, H.J., A.M. Lorrey, and J.A. Renwick, 2013: A Southwest Pacific Tropical Cyclone Climatology and Linkages to the El Nino Southern Oscillation. Journal of Climate, 26, 3-25. doi:10.1175/JCLI-D-12-00077.1.


Diamond, H.J., A.M. Lorrey, K.R. Knapp, and D.H. Levinson, 2012: Development of an enhanced tropical cyclone tracks database for the southwest Pacific from 1840-2010. International Journal of Climatology, 32, 2240-2250. doi:10.1002/joc.2412.


Levinson, D. H., H. J. Diamond, K. R. Knapp, M. C. Kruk, and E. J. Gibney, 2010: Toward a homogenous global tropical cyclone best track dataset. Bulletin of the American Meteorological Society, 91, 377-380. doi:10.1175/2010BAMS2930.1


Kruk, M. C., K. R. Knapp, and D. H. Levinson, 2010: A technique for merging global tropical cyclone best track data. Journal of Atmospheric and Oceanic Technology, 27,680-692. doi:10.1175/2009JTECHA1267.1


Knapp, K. R., and M. C. Kruk, 2010: Quantifying Interagency Differences in Tropical Cyclone Best-Track Wind Speed Estimates. Monthly Weather Review, 138, 1459-1473. doi:10.1175/2009MWR3123.1.


Levinson, D. H., and H. J. Diamond, 2009: Combining Tropical Cyclone Data Sets Worldwide
Eos, 90. doi:10.1029/2009EO350006.


Knapp, K. R., M. C. Kruk, D. H. Levinson, and E. J. Gibney, 2009: Archive compiles new resource for global tropical cyclone research. Eos, Transactions, AGU., 90, 46. doi:10.1029/2009EO060002.