Many drifting buoys are deployed from ships and aircraft into the Gulf of Mexico and into the Atlantic and Pacific   Oceans.   Drifting   buoys   move   with   the prevailing  currents  and  automatically  report  observed meteorological   and   oceanographic   elements   via satellite. There are several types of drifting buoys, and not   all   buoys   transmit   the   same   package   of environmental  data.  Normally,  drifting  buoys  sample data continuously, but data is reported only when polar- orbiting  meteorological  satellites  pass  over  the  buoy positions. This occurs a minimum of twice a day. Information observed by drifting buoys is encoded in  WMO  International  Code  FM  18-XI  BUOY.  This code  contains  some  elements  similar  to  the  ship S y n o p t i c    c o d e    a n d    o t h e r s    s i m i l a r    t o    t h e Bathythermograph  code.  The  symbolic  format  of  the BUOY code is shown in table 2-3. The report contains 5 sections of data, identified as section 0 through section 4. Section 0 is identification information, and section 1 contains  meteorological  and  other  non-marine  data. Section  2  contains  surface  marine  data.  Section  3  is used  to  report  bathymetric  readings,  while  the  last section,  section  4,  is  used  to  report  engineering  and quality control data. SECTION 0  ZZYY  A₁b_wn_bn_bn_b  YYMMJ  GGggi_w Q_cL_aL_aL_aL_aL_a  L_oL_oL_oL_oL_oL_o  (6Q₁Q_tQ_A/) SECTION  1   111Q_dQ_x  0ddff  1s_nTTT 2S_nT_dT_dT_d or (29UUU) 3P_OP_OP_OP_O 4PPPP 5appp SECTION  2  222Q_dQ_x 0S_nT_wT_wT_w 1P_waP_waH_waH_wa 20P_waP_waP_wa 21H_waH_waH_wa SECTION   3333Q_d1Q_d2 8887k₂ 2Z_nZ_nZ_nZ_n 3T_nT_nT_nT_n 4S_nS_nS_nS_n (66k₆9k₃  2Z_nZ_nZ_nZ_n  d_nd_nc_nc_nc_n) SECTION 4  444 1Q_PQ₂Q_TWQ₄ 2Q_NQ_LQ_A/ Q_cL_aL_aL_aL_aL_a L_oL_oL_oL_oL_oL_o or  (YYMMJ  GGgg/  7V_BV_Bd_Bd_B)  8V_iV_iV_iV_i 9i_dZ_dZ_dZ_d Data from drifting buoys is relayed from satellites to   designated   sites   around   the   world,   where   the information  is  checked  for  validity  and  then  transmitted over  environmental  networks.  In  most  cases,  the  data  is already  received  from  the  buoy  in  the  ZZYY  format, and only the data quality indicators must be encoded. A  typical  drifting  buoy  report,  which  reports weather and ocean temperatures every 10 meters to 150 meters, would appear similar to the following: SSVX06 KARS 231145 ZZYY 93503 23027 11454 712238 095139 11119 00308 10255 29075 30132 40133 52003 22219 00262 10302 33311 88870 20010 31820 20020 31252 20030 31103 20040 31055 20050 31037 20060 31027 20070 31002 20080 31002 20090 30944 20100 30915 20110 30891 20120 30830 20130  30876 20140 30844 20150 30819 66091 20150 18135 444 201// 23027 1000/ 71227 81101 90150; Other  than  the  information  in  the  buoy identification  section,  all  other  data  is  optional;  it  is reported  only  when  available.  Many  drifting  buoys Table 2-3.—Symbolic Format of WMO Code FM 18-XI BUOY report surface conditions until the battery fails (about 6 to   12   months),   but   only   report   subsurface temperatures/currents/depths for the first 3 to 6 months after deployment, the engineering life of the "tails." IDENTIFICATION  SECTION All code groups in section 0 must be included in each  report  with  the  exception  of  the  last  group.  All buoy  reports,  even  those  grouped  within  a  collective bulletin, begin with the data type identifier "ZZYY." Group   A₁b_wn_bn_bn_b  is  the  WMO  assigned  area, block,  and  identification  number  of  each  individual buoy.  The  number  is  assigned  before  the  buoy  is deployed, based on the intended deployment location. This number will remain the same throughout the life of the buoy. In our example, the buoy identifier is 93503. Groups  YYMMJ  (the  day,  month,  and  year)  and GGggi_w   are   nearly   identical   to   the   bathy   code identification groups. except for the indicator i_w used as the last digit of the group. This code figure is used to indicate the units of wind speed (1 = meters per second, 4  =  knots).  In  our  example,  the  date  and  time  of  the observation are provided by 23027 11454, for the 23d of February,  1997,  at  11452.  The  indicator  4  shows  the wind is measured in knots. The   buoy’s   position   is   given   by   the   groups Q_cL_aL_aL_aL_aL_a  L_OL_OL_OL_OL_OL_O.  Notice  that  these  are each  6-digit  groups  instead  of  the  standard  5-digit groups. As in the bathy code, Q_c is quadrant of the globe from  WMO  code  table  3333  (refer  to  Appendix  III). However,   L_aL_aL_aL_aL_a  is  the  latitude  to  the  nearest thousandth  of  a  degree  (3  decimal  places).  Likewise, L_oL_oL_oL_oL_oL_o   is   the   longitude   to   the   nearest thousandth of a degree. A report may replace the last figure in each group with a slant if the position is only reported  to  the  nearest  hundredth  of  a  degree.  For example,  712238  095139  would  report  a  position  in 2-18