This corrigendum is to report two known errors in Knaff et al. (2014) entitled “An objective satellite-based tropical cyclone size climatology.” Both errors are in equations, namely Eqs. (2) and (3).

To remind the reader, Eq. (2) uses a satellite-based estimate of the tangential wind at 500 km (V500) to estimate tropical cyclone (TC) size or R5, which is defined as the radius of where the TC wind field is indistinguishable from the background flow in a climatological environment. The error in Eq. (2) is related to parameter constants used to estimate R5 from V500:

 
formula

In our paper, the climatological values of the V500 (V500c) and of the tangential wind at 1000 km (V1000c) are needed to estimate R5. An error was introduced by incorrectly estimating the term V1000c. As stated in our paper, V1000c was incorrectly estimated by multiplying the average vorticity (r = 0–1000 km), ζ1000, by the radius, that is V1000c = rζ1000. This relationship results in V1000c estimates that are a factor of 2 too large. The correct estimate of V1000c should have been calculated using the relationship V1000c = rζ1000/2.0. As a result Eq. (2) should have the following parameter constants: = 734 km, V1000c = 1.12 m s−1, and V500c = 5.05 m s−1. This change to the scaling results in incorrect statistics being listed in Tables 1, 3, 4, and 5 and errors in the distributions shown in Fig. 4. The incorrect scaling also results in incorrect (or biased) y-axis values for life cycle composites shown in Fig. 5 and for long-term trend results shown in Fig. 9. The revised tables and a revised Fig. 4 are provided here. However, since the important aspects of life cycle behavior/evolution of R5, shown in Fig. 5, and the long-term trends, shown in Fig. 9, are well portrayed, though biased, using the original R5 values, corrected versions of those figures are not provided in this corrigendum. Note that the original R5 values are biased ~33% too large.

Table 1.

General statistics related to the V500 and R5 estimates. V500 is estimated by (1) and R5 is estimated by (2). Units for V500 and R5 are m s−1 and DDLAT, respectively, where 1 DDLAT = 111 km.

General statistics related to the V500 and R5 estimates. V500 is estimated by (1) and R5 is estimated by (2). Units for V500 and R5 are m s−1 and DDLAT, respectively, where 1 DDLAT = 111 km.
General statistics related to the V500 and R5 estimates. V500 is estimated by (1) and R5 is estimated by (2). Units for V500 and R5 are m s−1 and DDLAT, respectively, where 1 DDLAT = 111 km.
Table 3.

Statistics associated with Fig. 4. Shown are the intensity category, the number of cases, the mean (R5), standard deviation [σ(R5)] and skew [Skew(R5)] of R5, intensity (Vmax), and latitude. The units for R5 and Vmax are DDLAT (where 1 DDLAT = 111 km) and kt, respectively.

Statistics associated with Fig. 4. Shown are the intensity category, the number of cases, the mean (R5), standard deviation [σ(R5)] and skew [Skew(R5)] of R5, intensity (Vmax), and latitude. The units for R5 and Vmax are DDLAT (where 1 DDLAT = 111 km) and kt, respectively.
Statistics associated with Fig. 4. Shown are the intensity category, the number of cases, the mean (R5), standard deviation [σ(R5)] and skew [Skew(R5)] of R5, intensity (Vmax), and latitude. The units for R5 and Vmax are DDLAT (where 1 DDLAT = 111 km) and kt, respectively.
Table 4.

Statistics associated with the upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 6. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are listed. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.

Statistics associated with the upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 6. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are listed. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.
Statistics associated with the upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 6. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are listed. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.
Table 5.

Statistics associated with the basin-specific upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 7. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are provided. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.

Statistics associated with the basin-specific upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 7. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are provided. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.
Statistics associated with the basin-specific upper and lower quartiles of TC size (R5) for minor and major hurricane intensity TCs at the time of first maximum lifetime intensity shown in Fig. 7. The number of cases (No.), the mean, and the standard deviation (σ) associated with each quartile are provided. Means and standard deviations have units of DDLAT, where 1 DDLAT = 111 km.
Fig. 4.

Frequency distributions of TC size (R5) for the (a) North Atlantic, (b) eastern North Pacific, (c) western North Pacific, (d) north Indian Ocean, and (e) Southern Hemisphere tropical cyclone basins. Blue lines, black lines, and red lines are associated with tropical storm, minor hurricane, and major hurricane intensities respectively as indicated in the key (see text for additional information). Units of R5 are distance in degrees latitude (DDLAT, where 1 DDLAT = 111 km).

Fig. 4.

Frequency distributions of TC size (R5) for the (a) North Atlantic, (b) eastern North Pacific, (c) western North Pacific, (d) north Indian Ocean, and (e) Southern Hemisphere tropical cyclone basins. Blue lines, black lines, and red lines are associated with tropical storm, minor hurricane, and major hurricane intensities respectively as indicated in the key (see text for additional information). Units of R5 are distance in degrees latitude (DDLAT, where 1 DDLAT = 111 km).

A second error involves Eq. (3), which should be in terms of V500 and not R5. Thus the proper equations should be as follows:

 
formula

We sincerely apologize for our mistakes and hope this corrigendum does not reflect poorly on the paper’s overall quality. It is important to note that the conclusions about where small and large TCs form, how TC size changes as a function of initial size, intensity evolution, and poleward displacement, and the trends in TC size over the last 30 years still hold.

Acknowledgments

We thank Dr. Dan Chavas for bringing the scaling error to our attention and Megan Troutman for her assistance with the corrected figure and tables. The views, opinions, and findings contained in this report are those of the authors and should not be construed as an official National Oceanic and Atmospheric Administration or U.S. government position, policy, or decision.

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