Annual Solar Wind Speed Maps

Synoptic Source Surface Maps in the Carrington Rotation Number versus Heliographic Latitude.
The Source Surface was assumed to be at 2.5 solar radii. The IPS-CAT method was applied to derive these maps. The data file for each year includes 11 CRs.

Note: "dat 1" from the CAT analysis using only V data (Tokumaru et al., 922:73, 2021).

Sample Fortran program to read the data
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PARAMETER (nlota=11,nlon=nlota*360,nlat=180)
c                    =11 rotations*360 deg
REAL      vg  (nlon,nlat)  ! for 11 rotations
 
Open(10,file=filename,status='old')
DO j=1,nlat
   DO i=1,nlon
      read(10,*) vg(i,j)
   ENDDO
ENDDO
Close(10)
 
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References:
Kojima, M., M. Tokumaru, H. Watanabe, A. Yokobe, K. Asai, B.V. Jackson, and P.L. Hick,"Heliospheric tomography using interplanetary scintillation observations, II. Latitude and heliocentric distance dependence of solar wind structure at 0.1-1 AU",Journal of Geophysical Research, 103, pp1981-1989, 1998.
Kojima, M., M. Tokumaru, K. Fujiki, K. Hayashi, and B. V. Jackson,"IPS tomographic observations of 3D solar wind structure", Astronomical and Astrophysical Transactions, 26, No. 6, 467-476, 2007.
Tokumaru, M., M. Kojima, and K. Fujiki, "Solar cycle evolution of the solar wind speed distribution from 1985 to 2008", Journal of Geophysical Research, 115, A04102, 2010 (doi:10.1029/2009JA014628).
Tokumaru, M., M. Kojima, and K. Fujiki, "Long-term evolution in the global distribution of solar wind speed and density fluctuations during 1997-2009", Journal of Geophysical Research, 117, A06108, 2012 (doi:10.1029/2011JA017379).

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