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                             Meteorology Data
                                 from the
                     Marginal Ice Zone Experiments
                   (MIZEX-83, MIZEX-84 and MIZEX-87)
                                  and the
               Coordinated Eastern Arctic Experiment (CEAREX)

1.  Introduction                                                          
                                                                          
1.1  Documentation structure                                              
                                                                          
       1. This introduction                                               
       2. Description of Data File Format on CD-ROM                       
          2.1 Surface Data Files                                          
          2.2 Rawinsonde Profile Data                                     
       3. MIZEX-83                                                        
          3.1 Overview of MIZEX-83 Meteorology                            
          3.2 Instrumentation and Data Accuracy - POLARBJORN              
       4. MIZEX-84                                                        
          4.1 Overview of MIZEX-84 Meteorology                            
          4.2 Instrumentation and Data Accuracy - POLAR QUEEN             
          4.3 Instrumentation and Data Accuracy - HAAKON MOSBY            
          4.4 Instrumentation and Data Accuracy - POLARSTERN              
          4.5 Instrumentation and Data Accuracy - VALDIVIA                
        5. MIZEX-87                                                       
          5.1 Overview of MIZEX-87 Meteorology                            
          5.2 Instrumentation and Data Accuracy - POLAR CIRCLE            
          5.3 Instrumentation and Data Accuracy - HAAKON MOSBY            
          5.4 Instrumentation and Data Accuracy - VALDIVIA                
        6. CEAREX                                                         
          6.1 Overview of CEAREX Meteorology                              
          6.2 Instrumentation and Data Accuracy - POLARBJORN              
          6.3 Instrumentation and Data Accuracy - HAAKON MOSBY            
          6.4 Instrumentation and Data Accuracy - "O" Camp                
          6.5 Instrumentation and Data Accuracy - "A" Camp                
        7. Acknowledgments                                                
        8. References                                                     
        9. Contact Information                                            
                                                                          
1.2  Meteorology Documentation Overview                                   
                                                                          
       The data described here represent basic meteorological parameters  
obtained during the Marginal Ice Zone Experiments in 1983, 1984, 1987     
(MIZEX-83,84,87) and the Coordinated Eastern Arctic Experiment (CEAREX), in
September 1988 - May 1989.  These were multi-national, interdisciplinary  
projects which took place during various seasons in the seas around the   
Svalbard archipelago.                                                     
                                                                          
       Data files on this CD-ROM contain two types of meteorological data:
near-surface (also called surface) time series of wind, pressure, temperature,
and humidity; and rawinsonde (also called upper-air or sounding) profiles of
the same parameters.  The format of these files is described in section 2.
                                                                          
       This documentation is organized by field program.  Each section    
begins with an overview of the field operations that are pertinent to the 
meteorological data.  Following this, instrumentation and data accuracy are
described for each platform.  The accuracies represent 95% confidence     
intervals based on manufacturer's claims, field experience, and knowledge 
of instrument location.  In general, the sensitivity of the instruments was
at least one order of magnitude greater than the accuracy.  Although      
considerable effort has been made to remove erroneous data, it is likely  
that a few bad data points remain.                                        
                                                                          
       Platform movement was vector subtracted from the measured wind     
velocity (relative wind) to give the true wind speed and direction.  The 
velocities of the ship platforms were determined from bridge heading and 
speed instruments.                                                          
                                                                          
        Additional information and graphical plots of the data are contained
in hard-copy meteorological atlases (Lindsay, 1984; Lindsay, 1985; Lindsay,
1986; Guest and Davidson, 1988; Lackmann et al., 1989; Guest and Davidson,
1989; Frederickson, which are available upon request.  See section 8 for the 
complete citations.  Information not presented here but contained in the atlases 
includes maps of sea level pressure analyses, maps of platform and ice edge positions, 
and radiation information in some cases.
                                                                          
        All times in the data set and documentation are Universal Time    
Convention, UTC.                                                         
                                                                          
        Important Note:  It was recently discovered that the humidity     
measurements from the Coastal Climate WeatherPak meteorological stations 
are highly suspect during cold conditions.  Therefore, consider all the  
humidity values from the MIZEX-87 and CEAREX surface data files to be    
suspect when the air temperature is below -10 degrees C.  Contact Peter  
Guest (address in section 9) for details.  The upper-air humidities are  
not affected.                                                            
                                                                          
 2.  Description of Data File Format on CD ROM                            
                                                                          
        The METEOR directory on this CD-ROM contains subdirectories for the
two types of data files, METEOR\SURFACE (12 surface data sets), and           
METEOR\UPPER (10 upper-air sounding data sets).  Files in the METEOR\         
SURFACE subdirectory are ASCII coded 80 character records.  Files in the      
METEOR\UPPER subdirectory are ASCII coded 81 character records.  The final    
character in each record is a carriage-return.  The variables within each     
record are separated by at least one space.                                   
                                                                             
 2.1.  Surface Data Files                                                    
                                                                             
        These files contain time series of surface wind speed, wind direction,
air temperature, relative humidity and pressure values.                     
                                                                            
      Filename                                                             
      MIZ83PB.SFC : MIZEX83 -POLARBJORN.   (5,796 RECORDS)                 
      MIZ84HM.SFC : MIZEX84  HAAKON MOSBY. (1,641 RECORDS)                  
      MIZ84PQ.SFC : MIZEX84- POLAR QUEEN.  (6,311 RECORDS)                 
      MIZ84PS.SFC : MIZEX84- POLARSTERN    (3,599 RECORDS)                 
      MIZ84VL.SFC : MIZEX84- VALDIVIA.       (168 RECORDS)                 
      MIZ87HM.SFC : MIZEX87- HAAKON MOSBY. (2,732 RECORDS)                 
      MIZ87PC.SFC : MIZEX87- POLAR CIRCLE. (2,759 RECORDS)                 
      MIZ87VL.SFC : MIZEX87- VALDIVIA.       (105 RECORDS)                 
      CRXACMP.SFC : CEAREX - A CAMP.       (2,689 RECORDS)                 
      CRXHM.SFC   : CEAREX - HAAKON MOSBY. (3,431 RECORDS)                 
      CRXOCMP.SFC : CEAREX - O CAMP.       (3,580 RECORDS)                 
      CRXPB.SFC   : CEAREX - POLARBJORN.  (34,913 RECORDS)            
                                                                           
         Every surface data record has the same format.  The time on each
record represents the start of a ten-minute averaging period (except VALDIVIA,
see section 4.5 and section 5.4 of this documentation file).  Missing data 
have the value -99.0 for surface data.

     The following FORTRAN program will read any of the surface data files:                                       
                                                                            
      INTEGER YEAR,MONTH,DAY,HOUR,MINUTE
   1  READ(7,10,END=99)YEAR,MONTH,DAY,HOUR,MINUTE,UTR,WDT,TA,RH,PR
  10  FORMAT(5(1X,I2),5(1X,E11.4)
      GOTO 1
  99  STOP
      END
                                                                           
    VARIABLE DEFINITIONS:                                                  
                                                                           
    1.  YEAR       - Universal Time Convention (UTC)                       
    2.  MONTH      -                                                       
    3.  DAY        -                                                       
    4.  HOUR       -                                                       
    5.  MINUTE     -                                                       
    6.  UTR        -  TRUE WIND SPEED (m/s)                                
    7.  WDT        -  TRUE WIND DIRECTION (Degrees Azimuthal)              
    8.  TA         -  AIR TEMPERATURE (C)                                  
    9.  RH         -  RELATIVE HUMIDITY (%)                                
   10.  PR         -  SURFACE PRESSURE (mb)                                
                                                                           
2.2.  Rawinsonde Profile Data                                              
                                                                           
       These files contain the rawinsonde profile data.  Listed below are  
the number of profiles and total records in each file.                     
                                                                        
     Filename                            # Soundings    # Records
     MIZ84HM.AIR : MIZEX84 -  HAAKON MOSBY        134        42069
     MIZ84PQ.AIR : MIZEX84 -  POLAR QUEEN          99        38208
     MIZ84PS.AIR : MIZEX84 -  POLARSTERN          217        73109
     MIZ84VL.AIR : MIZEX84 -  VALDIVIA            107        43916
     MIZ87HM.AIR : MIZEX87 -  HAAKON MOSBY         60        19085
     MIZ87PC.AIR : MIZEX87 -  POLAR CIRCLE         67        16398
     MIZ87VL.AIR : MIZEX87 -  VALDIVIA             53        13786
     CRXHM.AIR   : CEAREX  -  HAAKON MOSBY         93        27061
     CRXOCMP.AIR : CEAREX  -  "O" CAMP             66        18797
     CRXPB.AIR   : CEAREX  -  POLARBJORN          467       128881          
                                                                 
       The rawinsonde profile data files contain two types of records:  A  
single header record at the beginning of each sounding, followed by several
data records with the profile information collected as the balloon goes up. 
The header record contains:
                                                                           
      1. LOC    Platform label , i.e. MIZEX84HM, CEAREXPB etc.             
      2. XLAT   Latitude (Degrees North)                                   
      3. XLON   Longitude (Degrees East are positive, Degrees West are     
                negative)                                                  
      4. IDATE  Date (YYMMDD; i.e. Year, Month of Year, Day of Month)      
      5. ITIME  Time at start of sounding (HHMM); i.e. Hour, Minute        
      6. IMAX   Number of records in the sounding                          
                                                                           
      The profile data records contain:                                    
                                                                           
      1. RCOUNT Record counter for sounding = 1.0 to IMAX                  
      2. TA     Air temperature (Degrees C)                                
      3. TD     Dewpoint temperature (Degrees C)                           
      4. RH     Relative humidity (%)                                      
      5. PR     Pressure (mb)                                              
      6. WD     Wind direction (azimuthal)                                 
      7. WS     Wind speed (m/s)                                           
      8.  Z     Height (m)                                                 
                                                                            
      If one of the above variables has a value of -999.0, then the value of
that quantity was not available or was invalid.

     The following FORTRAN program will read any of the upper-air files.                              
                                                                           
      CHARACTER*9 LOC                                                      
**   READ HEADER **                                                        
  5   READ(8,20,END=400) LOC,XLAT,XLON,IDATE,ITIME,IMAX                    
 20   FORMAT(A9,2F10.4,3I10)                                               
**   READ THE DATA **                                                      
        DO 200 I=1,IMAX                                                    
          READ(8,30) RCOUNT,TA,TD,RH,PR,WD,WS,Z                           
   30     FORMAT(8(F10.3))                                                
  200   CONTINUE                                                          
      GO TO 5                                                           
  400 STOP                                                                
      END                                                                 
                                                                          
3.  MIZEX-83                                                              
                                                                          
3.1 Overview of MIZEX-83 Meteorology                                      
                                                                          
     The 1983 Marginal Ice Zone Experiment occurred in the East Greenland 
Sea marginal ice zone (MIZ) during the summer.  The data files presented  
here contain values of surface meteorological parameters from the POLARBJORN,
an ice-strengthened vessel.  Data collection began when the ship left the  
port of Tromso at 1800 UTC 14 July 1983.  The marginal ice zone (MIZ) was 
entered at 600 UTC 18 July.  The ship operated within the MIZ until 300   
UTC 30 July with the exception of the following two breaks.  From 1200 UTC
19 June to 2100 UTC 24 June the ship went to New Alesund, then to another 
fjord in northern Svalbard and finally to and from Longyearbyen for       
helicopter repairs.  From 1700 UTC 11 July to 2000 UTC 12 July the ship   
travelled to and from Longyearbyen for personnel rotation.                
                                                                          
     From 1200 UTC 27 June to 1730 UTC 8 July the POLARBJORN remained     
moored to the same large floe.  After 13 July the ship made stops at six  
ice floes for periods of several hours.  The rest of the time the ship was
usually in motion or undertaking oceanographic CTD measurements.          
                                                                          
3.2  Instrumentation and Data Accuracy - MIZEX-83 POLARBJORN              
                                                                          
3.2.1  Surface Measurements - POLARBJORN                                  
                                                                          
     The data on this CD-ROM represent averages from consecutive ten-minute 
periods.  The instruments were located on a bow mast, 16 meters above sea 
level.  The relative wind speed and direction were measured with a cup    
anemometer and a vane.  Temperature was obtained from an aspirated,       
radiation-shielded, platinum-resistance thermometer (PRT).  Humidity was  
obtained from a cooled-mirror hygrometer.  Pressure was not measured.     
                                                                          
     The temperature was accurate to within 0.5 degrees C and the humidity
to within 3% relative humidity.  Wind speed and direction were usually    
accurate to 0.3 m/s and 10 degrees respectively.  There were some brief   
periods when the wind measurements were less accurate due to ship-induced 
air flow distortion.                                                      
                                                                          
3.2.2  Upper-Air Measurements - POLARBJORN                                
                                                                          
     Rawinsonde measurements were obtained and summarized in "Radiosonde  
Observations from the POLARBJORN, MIZEX 83" (Lindsay, R.W., 1984, Polar   
Science Center, University of Washington, Technical Report, 280 pp.)  They
are not contained on this CD-ROM.  Inquire at NSIDC for current           
availability of these data.                                               
                                                                          
4. MIZEX-84                                                               
                                                                          
4.1  Overview of MIZEX-84 Meteorology                                     
                                                                          
     The 1984 Marginal Ice Zone Experiment (MIZEX-84) field program took  
place in the East Greenland Sea during the summer of 1984.  The MIZEX-84  
meteorological program was much more extensive than MIZEX-83.  This CD-ROM
contains surface and upper-air data from four ships:  POLAR QUEEN, HAAKON 
MOSBY, POLARSTERN and VALDIVIA.  Identical Vaisala Upper Air Sounding     
systems on all four ships measured upper-air parameters several times a   
day.                                                                      
                                                                          
     The field program commenced on 3 June when the ice-strengthened POLAR
QUEEN left port, and was completed on 21 July.  The POLAR QUEEN was usually
within the ice pack tens of kilometers from the edge.  The normal-hulled  
HAAKON MOSBY generally remained a few kilometers seaward of the ice edge. 
The normal-hulled VALDIVIA operated in the open ocean, usually tens of    
kilometers from the edge.  The ice-breaker POLARSTERN operated deep within
the pack ice, along the ice edge and in the open ocean.                   
                                                                          
     From 9 July to 13 July there was an intensive meteorological         
measurement period when rawinsondes were launched every 3 hours from each 
ship.  The ships remained in the same position to form a diamond-shaped   
pattern across the ice edge during this period.                           
                                                                          
4.2  Instrumentation and Data Accuracy - MIZEX 84 POLAR QUEEN             
                                                                          
4.2.1  Surface Measurements - POLAR QUEEN                                 
                                                                          
     During most of MIZEX-84, the POLAR QUEEN was moored to a large ice   
floe.  Near-surface wind speed and air temperature were measured at four  
levels from a 6.7 meter profile mast located on the floe 60 meters from the
ship.  The profile enabled the wind speed to be measured with an accuracy 
of 0.1 m/s.  Temperature was accurate to 0.1 degree C.                    
                                                                          
     When the profile mast was not deployed, during transit periods, or   
when the profile mast had an upwind obstruction, the wind and temperature 
was measured at 16 meters elevation from a bow mast on the ship.  During  
these times, the accuracies for wind speed and temperature were estimated 
to be 0.3 m/s and 0.5 degree C.  In all cases, the wind speed was adjusted to
the 10 meter value using standard flux-profile relationships.  Both the ice
tower and bow mast locations had cup anemometers and radiation-shielded   
aspirated platinum-resistance thermometers.                               
                                                                          
     Wind direction was measured with a vane on the bow mast with an      
accuracy of 5 degrees.  The wind vane was not operational before 11 June, 
therefore wind direction and wind speed, when the ship was moving, were not
available.  Humidity was measured with a cooled-mirror hygrometer on the bow
mast and was accurate to 3% relative humidity.  Pressure was measured in   
the ship's laboratory with an accuracy of 2 mb.  All values are ten-minute 
averages.                                                                  
                                                                           
     A data set described in section II.B. of "MIZEX 84 Integrated Surface 
Meteorological Data Set and Meteorological Atlas, 2nd edition" (Lindsay,   
R.W., 1985, Polar Science Center, University of Washington, Technical      
Report, 240 pp.), and available on 9-track tape from NSIDC, contains extra 
variables that flag suspect values of wind speed, wind direction,          
temperature and humidity.  A future CD-ROM may include the data on this    
tape; inquire at NSIDC for availability.                                   
                                                                           
4.2.2  Upper-Air Measurements - POLAR QUEEN                                
                                                                           
     Rawinsondes were launched from the ship at least twice a day under the 
direction of R. Lindsay from the Polar Science Center, using a Vaisala Upper
Air Sounding system.  The rawinsondes and initial processing of the data were
provided by the Alfred Wegener Institute for Polar Research (AWI) under the 
direction of E. Augstein and M. Gube-Lenhardt.                              
                                                                           
     The accuracy of the temperature and dewpoint temperature was 0.2      
degree C and 1.0 degree C respectively, while height was accurate to 30 m. 
Vector wind was accurate to 2.0 m/s.  However, the reader should be        
cautioned that rawinsonde measurements are instantaneous and do not        
necessarily represent average conditions, particularly if strong secondary 
circulations are present.                                                  
                                                                           
4.3  Instrumentation and Data Accuracy - MIZEX 84 HAAKON MOSBY             
                                                                           
4.3.1  Surface Measurements                                                
                                                                           
     The surface data from the HAAKON MOSBY were obtained using instruments 
similar to those on the POLAR QUEEN.  The wind, air temperature and humidity
probes were mounted on a platform extending forward of the HAAKON MOSBY's  
main mast at a height of 15 meters above sea level.  Pressure was measured 
in the ship's laboratory.  The accuracies were:  wind speed, 0.3 m/s; wind 
direction, 10 degrees; air temperature, 0.5 degree C; relative humidity, 3%;
pressure, 2 mb.  All observations were averaged over 10-minute intervals.  
The accuracy of the wind measurements was worse when the winds were directly
from the stern.                                                            
                                                                           
4.3.2  Upper-Air Measurements - HAAKON MOSBY                              
                                                                          
     Rawinsondes were launched four times a day or more under the direction
of K. Davidson.  The processing of the data and the estimated accuracies   
were identical to those for the POLAR QUEEN.                              
                                                                          
4.4  Instrumentation and Data Accuracy - MIZEX 84 POLARSTERN               
                                                                           
4.4.1  Surface Measurements - POLARSTERN                                   
                                                                           
     The data were supplied by M. Gube-Lenhardt.  The ship had two         
anemometers, wind vanes, and temperature sensors.  The set of sensors from 
the side of the ship from which the wind was blowing was used.  If the two 
wind vanes could not agree on which side that was, the side with the higher
wind speed was used.  The humidity was calculated from an Li-Cl sensor.    
The values represent ten-minute averages.  The accuracies are similar to   
those quoted above for the HAAKON MOSBY data set.                          
                                                                           
4.4.2  Upper-Air Measurements - POLARSTERN                                 
                                                                           
     The rawinsondes were usually launched every three hours by personnel  
from Alfred Wegener Institute for Polar Research.  The processing of the   
data and the estimated accuracies were identical to the POLAR QUEEN data
set.
                                                                       
4.5  Instrumentation and Data Accuracy - MIZEX 84 VALDIVIA                 
                                                                            
4.5.1  Surface Measurements - VALDIVIA                                      
                                                                           
     The data were supplied by M. Gube-Lenhardt.  The data were based on   
manually-recorded observations of the permanent ship instruments.  The     
observations were usually made every three hours and are based on averages 
over a few seconds.  Sometimes the wind speed was estimated from sea state. 
Pressure was obtained from a barometer on the bridge.  Humidity was not    
measured.  The accuracies were:  wind speed, 2.0 m/s; wind direction,      
15 degrees; air temperature, 1.0 degree C; pressure, 2 mb.                 
                                                                           
4.5.2  Upper-Air Measurements - VALDIVIA                                   
                                                                           
     The rawinsondes were usually launched every six hours.  The processing
of the data and the estimated accuracies were identical to the POLAR QUEEN 
data set.                                                                  
                                                                           
5. MIZEX-87                                                                
                                                                           
5.1  Overview of MIZEX-87                                                  
                                                                           
     The 1987 Marginal Ice Zone Experiment (MIZEX-87) was the third and    
final of the MIZEX experiments.  The field program occurred 19 March to 9  
April in the Greenland Sea and 10 April to 11 April in the Barents Sea near
Bear Island.  Surface and upper-air data were obtained from three ships:   
POLAR CIRCLE, HAAKON MOSBY and VALDIVIA.                                   
                                                                           
     The ice-strengthened POLAR CIRCLE was usually within the ice a few    
kilometers from the ice edge.  The HAAKON MOSBY operated just seaward of   
the ice edge.  The VALDIVIA operated in the open ocean near the ice edge to
tens of kilometers from the edge.                                          
                                                                           
5.2  Instrumentation and Data Accuracy - MIZEX 87 POLAR CIRCLE             
                                                                           
5.2.1  Surface Measurements - POLAR CIRCLE                                 
                                                                           
     The POLAR CIRCLE collected data from 22 March through 11 April.  A    
Coastal Climate WeatherPak meteorological station was located on a platform 
extending forward of the POLAR CIRCLE's bow mast at a height of 16 meters  
above sea level.  This instrument measured wind speed and direction,       
temperature, and relative humidity.  There was a bug in the WeatherPak     
software in the wind speed calculation when the wind speed was greater than
9 m/s.  During these periods, wind speed was measured from sonic           
anemometers at the same location.  There was excellent agreement (within   
0.3 m/s) between these sensors at lower wind speeds; therefore reported    
speeds should be accurate to at least this amount.  The errors associated  
with distortion of airflow by the ship were believed to be less than 5%    
because the anemometer locations were well away from blocking structures.  
An exception was when the wind was directly from the stern, when errors may 
have been as great as 20%.  The temperature was accurate to 1.0 degree C and
the relative humidity to within 5%.                                         
                                                                           
     Important Note:  It was recently discovered that the humidity         
measurements from the Coastal Climate WeatherPak meteorological stations   
are highly suspect during cold conditions.  Therefore, consider all the    
humidity values in this file to be suspect when the air temperature is     
below -10 degrees C.  Contact Peter Guest (address in section 9) for       
details.  The upper-air humidities are not affected.                       
                                                                           
     All the wind speed and direction values on this CD-ROM for all the    
ships were corrected for ship motion based on the ship's speed and         
heading.  On the POLAR CIRCLE the ship's heading was obtained from a       
compass on the WeatherPak and was routinely checked against the ship's     
gyroscope.  Unfortunately, the ship caused extreme magnetic distortion     
for certain headings so that there were occasionally considerable errors   
in the true wind directions between the times when the gyroscope heading   
was recorded.  When the POLAR CIRCLE was near the HAAKON MOSBY, the wind   
direction from the latter should be used.  Most of the time the wind       
directions from the POLAR CIRCLE were accurate to within 20 degrees.  This 
problem did not affect the true wind speed calculations.  The data were    
averaged over ten-minute periods.                                          
                                                                           
5.2.2  Upper-Air Measurements - POLAR CIRCLE                               
                                                                           
     Vertical profiles of temperature, humidity and winds were obtained    
using a rawinsonde system manufactured by the VIZ Corporation nominally    
every six hours.  The vector winds were determined from an Omega           
navigation system on the rawinsondes and were usually accurate to 1.0 m/s. 
[Omega is a world-wide radio navigation system providing navigational      
parameters by phase comparison of very-low-frequency (10-14 KHz),          
continuous-wave radio signals. (McGraw-Hill Dictionary of Scientific and   
Technical Terms, 2nd edition, 1978.)]  In regions of strong vertical shear,
errors may increase to 2.0 m/s.  The temperature and dewpoint temperature  
were accurate to 0.2 degree C and 1.0 degree C respectively, while the     
heights were accurate to 30 meters.  Note that rawinsonde measurements are 
instantaneous and do not necessarily represent the average conditions,     
particularly when strong secondary circulations are present.               
                                                                           
5.3  Instrumentation and Data Accuracy - MIZEX 87 HAAKON MOSBY             
                                                                           
5.3.1  Surface Measurements - HAAKON MOSBY                                 
                                                                           
     The HAAKON MOSBY had a Coastal Climate WeatherPak meteorological      
station at 18 meters elevation with the same instruments and similar       
accuracies as the POLAR CIRCLE for all parameters except wind direction.   
At wind speeds above 11 m/s a miniature cup anemometer was used to measure 
wind speed since the WeatherPak software had a bug in the calculation of   
these wind speeds.  Unlike the POLAR CIRCLE, there was no magnetic         
distortion of the compass; therefore wind directions were usually accurate 
to 5 degrees.  During a few periods when air flow was from the stern of    
the ship, flow distortion may have caused 20% errors in wind speed and     
direction.  Ten-minute averages were recorded.                             
                                                                           
     Important Note:  It was recently discovered that the humidity            
measurements from the Coastal Climate WeatherPak meteorological stations   
are highly suspect during cold conditions.  Therefore, consider all the    
humidity values in this file to be suspect when the air temperature is     
below -10 degrees C.  Contact Peter Guest (address in section 9) for       
details.  The upper-air humidities are not affected.                       
                                                                           
5.3.2  Upper-Air Measurements - HAAKON MOSBY                               
                                                                           
     The rawinsondes launched from the HAAKON MOSBY were manufactured by    
the Vaisala Corporation using a system developed by R. Helvey of the        
Pacific Missile Test Center.  The rawinsondes were usually launched every   
six hours.  The temperature data obtained from these rawinsondes have an    
accuracy of 0.2 degree C and the dewpoint temperatures are accurate to      
within 1.5 degrees C.  Wind data were obtained using an Omega navigation    
tracking system on each rawinsonde.  The vector wind speeds were usually    
accurate to 2 m/s.  Winds in the lower 500 meters of the rawinsonde flights 
had to be interpolated from surface and upper-level measurements and        
therefore are likely to have larger errors.  The heights are accurate to    
within 30 meters.                                                           
                                                                            
5.4  Instrumentation and Data Accuracy - MIZEX 87 VALDIVIA                 
                                                                           
5.4.1  Surface Measurements - VALDIVIA                                      
                                                                            
     Instruments on the VALDIVIA measured all the basic parameters except   
humidity.  There was a problem recording the correct time; therefore this   
CD-ROM contains data collected only during standard observation periods,    
when the time was known.  This was usually every three hours.  The 
accuracies of the values were the same as those from the HAAKON MOSBY.    
                                                                            
     Important Note:  It was recently discovered that the humidity          
measurements from the Coastal Climate WeatherPak meteorological stations    
are highly suspect during cold conditions.  Therefore, consider all the     
humidity values in this file to be suspect when the air temperature is      
below -10 degrees C.  Contact Peter Guest (address in section 9) for        
details.  The upper-air humidities are not affected.                        
                                                                            
5.4.2  Upper-Air Measurements - VALDIVIA                                    
                                                                            
     The rawinsonde system on the VALDIVIA was virtually identical to the    
POLAR CIRCLE system and had the same accuracies.  Launches were usually     
performed every six hours.                                                  
                                                                            
6. CEAREX                                                                   
                                                                            
6.1  Overview of CEAREX Meteorology                                         
                                                                            
     The Coordinated Eastern Arctic Experiment began with the drift of the  
R/V POLARBJORN on 17 September 1988 and ended on 19 May 1989 when the       
POLARBJORN docked in Longyearbyen, Spitsbergen.  In addition to the         
POLARBJORN, the R/V HAAKON MOSBY and two ice camps were also used to       
collect meteorological data.                                                
                                                                            
6.1.1  CEAREX Drift Phase                                                   
                                                                            
     The drift phase lasted from September 1988 until early January 1989.   
During this period the POLARBJORN was moored to a large ice floe and was    
relatively immobile.  The POLARBJORN operated in the Fram Strait and        
Barents Sea areas from late January until May 1989.  The R/V HAAKON MOSBY   
(University of Bergen, Norway) was active from 25 February until 25 March   
1989.                                                                       
                                                                            
     During September 1988 the U.S. Coast Guard ice breaker NORTHWIND       
escorted the R/V POLARBJORN (Rieber Shipping, Alesund, Norway) far into a   
region of multiyear pack ice north of Svalbard.  A large ice floe ("Alpha"  
Floe) was selected, to which the POLARBJORN was moored on 17 September.     
From this time until 15 November the POLARBJORN drifted slowly southward    
with the ice pack; Alpha Floe was used as a drifting data collection        
platform.  Due to persistent northerly winds the POLARBJORN tracked east of 
Spitsbergen, passing within a few kilometers of the island of Kvitoya.  The 
combination of strong northwesterly winds and the ship's location just      
northwest of Kvitoya resulted in destruction of Alpha Floe on 15 November.  
At this time equipment was brought aboard and an attempt was made to return 
to Tromso, Norway.  After several days of limited progress, 16 of the 20    
scientists were airlifted to Spitsbergen on 12 December.  One meteorologist 
stayed aboard as the POLARBJORN worked slowly southward, maintaining data   
acquisition systems and continuing the twice daily soundings.  A strong     
storm in early January allowed the POLARBJORN to break free and return to   
Tromso on 9 January.                                                        
                                                                            
6.1.2  CEAREX Whaler's Bay / SIZEX Phase                                    
                                                                            
     The "Whaler's Bay" phase began on 13 January 1989, when the POLARBJORN 
sailed from Tromso in route to operations in Fram Strait.  The Seasonal Ice 
Zone Experiment (SIZEX) phase contained two separate cruises, the first     
lasting from 9 February until 5 March 1989, the second from 8 March until   
2 April 1989.  Bio-physical oceanographic operations commenced 4 April and  
concluded 17 May 1989.  The first SIZEX cruise concentrated on conditions   
in the vicinity of Bjornoya, south of Svalbard; all subsequent cruises      
were located in the Fram Strait region west of Svalbard.                    
                                                                            
     The HAAKON MOSBY's participation in SIZEX began on 25 February 1989,   
when the ship left Tromso, Norway, bound for regions in the Barents Sea.    
From 26 February to 7 March 1989 the ship operated in the general area      
between the Svalbard and the northern coast of Norway.  On 7 March the      
HAAKON MOSBY headed northwest toward regions in the Fram Strait west and    
southwest of Svalbard, where the ship cruised seaward of the pack ice edge  
from 11 to 19 March 1989.  The HAAKON MOSBY then headed southeast into the  
Barents Sea, finally returning to port on 23 March 1989.  During the period 
0800 UTC 25 February to 1400 UTC 23 March 1989, measurements of basic surface
meteorological parameters were taken every ten minutes.  From 2 to 23 March 
vertical soundings of the atmosphere were made approximately every six      
hours, weather and equipment permitting, and more frequently during         
interesting weather conditions.                                             
                                                                            
6.1.3  Camp Operations Phase                                                
                                                                            
     The oceanography ice camp ("O" Camp) was active from 30 March until 24 
April 1989; the acoustic ice camp ("A" Camp) operated from 30 March until   
20 April 1989.                                                              
                                                                            
     The "O" Camp and "A" Camp operations were located on the pack ice in   
the Fram Strait.  Most of the studies conducted at "O" Camp were related to 
processes in the upper boundary layer of the ocean.  The focus of "A" Camp  
was acoustics in the ocean.  Both camps were also the site of the           
meteorological measurements described here.                                 
                                                                            
     Meteorological measurements were obtained in 1989 during the periods   
1130 UTC 27 March - 1420 UTC 23 April and 1600 UTC 30 March - 0700 UTC 19   
April for "O" Camp and "A" Camp, respectively.  No rawinsondes were         
launched from "A" Camp.                                                     
                                                                            
6.2  Instrumentation and Data Accuracy - CEAREX - POLARBJORN                
                                                                            
6.2.1  Surface Measurements - POLARBJORN                                    
                                                                            
     A Coastal Climate WeatherPak meteorological station was located on a   
platform extending forward of the POLARBJORN's bow mast at a height of 14   
meters above sea level.  This instrument measured wind speed and direction, 
temperature, and relative humidity.  Temperature data are accurate to       
within 1.0 degree C and humidity to within 5%.  Accuracy of wind speed and  
direction depended on wind direction relative to the ship; a "sheltering"   
effect was observed with winds directly from the stern.  This situation     
seldom occurred during the drift phase due to the ship's slowly varying     
heading and persistent northerly winds.  Wind speeds are accurate to within 
0.3 m/s and direction to within 10 degrees, although during periods of      
unfavorable wind direction, errors may have been larger.                    
                                                                           
     Important Note:  It was recently discovered that the humidity          
measurements from the Coastal Climate WeatherPak meteorological stations    
are highly suspect during cold conditions.  Therefore, consider all the     
humidity values in this file to be suspect when the air temperature is        
below -10 degrees C.  Contact Peter Guest (address in section 9) for        
details.  The upper-air humidities are not affected.                        
                                                                            
     All winds were corrected for ship motion based on ship speed and       
heading.  Throughout most of the drift, ship and ice relative winds were    
within 0.5 m/s.  However, after 15 November when the POLARBJORN was mobile, 
this correction was important.                                              
                                                                            
6.2.2  Upper-Air Measurements - POLARBJORN                                  
                                                                            
     Vertical profiles of temperature, humidity, and wind speed and         
direction were obtained twice daily throughout the experiment, with         
additional launches during periods of extreme or unusual weather.  The      
system used rawinsondes and software developed by the VIZ Corporation.  The 
rawinsondes were equipped with thermistors that measured temperatures to    
within 0.2 degree C.  The humidity sensor consisted of a specially coated   
glass plate, the resistance across which varies with humidity.  Humidity    
measurements generally agreed quite well with Coastal Climate WeatherPak    
readings, although some overestimation was evident.  Winds were measured    
using Omega tracking and were therefore unavailable during periods of high  
solar flare activity.  [Omega is a world-wide radio navigation system       
providing navigational parameters by phase comparison of very-low-frequency 
(10-14 KHz), continuous-wave radio signals. (McGraw-Hill Dictionary of      
Scientific and Technical Terms, 2nd edition, 1978.)]                        
                                                                            
     A systematic underestimation of low-level winds occurred due to the    
necessary 3-minute averaging of all wind data.  Underestimation resulted    
from inclusion of lighter inversion-layer winds in the average.  Rawinsonde 
wind directions were generally accurate to within 20 degrees.  This data    
set includes virtually all rawinsonde data with very little editing.        
Spurious wind data take the form of shallow (100 meter) jets; the user of   
the data files is cautioned to be skeptical of any soundings exhibiting     
large vertical shear in the absence of a temperature inversion.             
                                                                           
     Altitude was measured with a baroswitch, occasionally yielding        
spurious contacts, particularly at low levels.  An effort was made to       
remove spurious contacts, but success in this difficult task is a function  
of operator experience, therefore inaccuracies may exist in some soundings. 
Errors of this type are always largest at higher levels because of the      
cumulative effect of erroneous contacts during the rawinsonde's ascent.     
                                                                            
6.3  Instrumentation and Data Accuracy - CEAREX - HAAKON MOSBY              
                                                                            
6.3.1  Surface Measurements - HAAKON MOSBY                                  
                                                                            
     A Coastal Climate WeatherPak meteorological station was used on board  
the HAAKON MOSBY to measure air temperature, relative humidity, atmospheric 
pressure, and wind speed and direction.  This station was mounted on a      
platform extending forward of the HAAKON MOSBY's bow mast at a height of 15 
meters above sea level.  All observations were averaged over ten-minute     
intervals.  The temperature data obtained from this instrument were         
accurate to within 1.0 degree C and the relative humidity data to within 5%.
The accuracy of the wind measurements depended on the wind direction        
relative to the ship; a "sheltering" effect was observed with winds blowing 
directly from the stern.  Wind speeds are accurate to within 0.3 m/s and    
direction to within 10 degrees, although when winds were from the stern the 
errors are likely to be larger.  All wind data have been corrected for ship 
motion based on ship speed and heading.  The measurements of atmospheric    
pressure are accurate to within 2 millibars.                                
                                                                            
     Important Note:  It was recently discovered that the humidity          
measurements from the Coastal Climate WeatherPak meteorological stations    
are highly suspect during cold conditions.  Therefore, consider all the     
humidity values in this file to be suspect when the air temperature is      
below -10 degrees C.  Contact Peter Guest (section 9) for details.  The     
upper-air humidities are not affected.                                      
                                                                            
6.3.2  Upper-Air Measurements - HAAKON MOSBY                                
                                                                            
     Vertical soundings of the atmosphere were routinely obtained roughly   
every six hours, with rawinsonde flights at approximately 0000, 0600, 1200  
and 1800 UTC every day, depending upon equipment or environmental           
difficulties.  During periods of unusual or exceptional weather conditions  
soundings were made more frequently.  The number of soundings made in a     
single day varied from zero to as many as nine.                             
                                                                            
     The vertical profiles of temperature, dew point temperature and wind   
speed and direction were measured using rawinsondes manufactured by the     
Vaisala Corporation and software developed by Roger Helvey.  The            
temperature data obtained from these rawinsondes have an accuracy of 0.2    
degree C and the dewpoint temperatures are accurate to within 1.5 degrees   
C.  Wind data were obtained using an Omega navigation tracking system on    
each rawinsonde.  The vector wind speeds are considered to be accurate to   
within 1 m/s.  Winds in the lower 500 meters of the rawinsonde flights had 
to be interpolated from surface and upper-level measurements and therefore  
are likely to have larger errors.  The heights are accurate to within 30    
meters.  Obvious errors in the profile data were removed but the data are   
otherwise unedited.                                                         
                                                                            
6.4  Instrumentation and Data Accuracy - CEAREX - "O" Camp                  
                                                                            
6.4.1  Surface Measurements - "O" Camp                                      
                                                                            
     Wind speed, wind direction, temperature, humidity and pressure were    
obtained from a Coastal Climate WeatherPak meteorological station and       
recorded on Hewlett-Packard 200 series computers.  The data were averaged   
over ten-minute periods.  The winds were measured at a height of 2.82 m     
above the ice surface.  Temperature, humidity and pressure were measured    
at 2.24 m.  The temperature was accurate to 0.5 degree C; relative humidity,
8.0%; wind speed, 0.2 m/s; wind direction, 5.0 degrees; and pressure,       
2.0 mb.  The pressure data show some high frequency fluctuations that are   
not believed to be real.                                                    
                                                                           
     Important Note:  It was recently discovered that the humidity          
measurements from the Coastal Climate WeatherPak meteorological stations    
are highly suspect during cold conditions.  Therefore, consider all the     
humidity values in this file to be suspect when the air temperature is     
below -10 degrees C.  Contact Peter Guest (address in section 9) for        
details.  The upper-air humidities are not affected.                        
                                                                            
     Computer and met station malfunctions created periods when data were   
missing or obtained from other instruments.  Considerable post-experiment   
editing was required to provide the best estimates of the basic met         
parameters.  The periods and substitution measurements when problems        
occurred will be described in the following paragraphs.                     
                                                                            
     A computer malfunction on 27 March forced me to manually record the    
met station data.  Therefore, on this day, the values of all parameters are 
based on 10-second average measurements with irregular intervals ranging    
from 4 to 90 minutes between recorded measurements.  No data were recorded  
between 1730 and 2240 UTC.  At 2240 UTC 27 March, the computer began        
working and normal (ten-minute met station averages) data collection        
occurred until 1710 UTC 28 March when computer failure again occurred.      
Later, the computer was fixed but the met station failed.  No data were     
obtained until 1340 UTC 30 March.                                           
                                                                            
     At 1340 UTC 30 March a sonic anemometer was deployed at a height of    
3.33 m.  It measured average wind speed and direction, with an accuracy     
of 0.3 m/s and 10 degrees, respectively, every ten minutes.  Air temperature
was recorded manually at 1405 and 1425 UTC 30 March using an unshielded     
alcohol thermometer located beside the hut 0.7 m above the surface.  On     
31 March and 1 April the alcohol thermometer was moved to a homemade box    
shield located 1.7 m above the surface.  The temperature was manually       
recorded hourly during these days, except for sleep periods, and was accurate
to within 1.5 degrees C.                                                    
                                                                            
     Beginning 2300 UTC 31 March, pressure from an altimeter in the camp    
manager's hut was recorded two or three times a day.  Starting at 1830 UTC  
2 April, the sonic anemometer was used to determine ten-minute average      
temperature.                                                                
                                                                            
     The pressure and temperature sensors described in the previous two     
paragraphs were calibrated later in the experiment when a replacement met   
station was available for comparison.  After adjusting for a bias, the      
above sensors compared very well with the met station and the accuracies    
were estimated to be at least as good as the met station accuracies, (2.0  
mb and 0.5 degree C, respectively).  It should be noted that temperature as
measured by a sonic anemometer is affected by humidity, but this is too    
small an effect in the Arctic to alter the accuracy stated above.          
                                                                           
     At 1930 UTC 9 April, a replacement met station was deployed and       
recorded average pressure, temperature, humidity and winds every ten       
minutes.  The heights and accuracies were the same as described earlier for
the met station.  The values recorded by this instrument were used for     
presentation in the atlas for the rest of the experiment, although the     
other sensors were still operational and provided intercomparisons for the 
post calibrations described above.                                         
                                                                           
     Therefore, with the exception of a gap from 1710 UTC 28 March to 1340 
UTC 30 March, all basic met parameters were obtained by at least one sensor
throughout the experiment on "O" Camp.  Humidity was the one exception; it 
was available only when the met station was operational.                   
                                                                           
6.4.2  Upper-Air Measurements - "O" Camp                                   
                                                                            
     Upper-air measurements of the basic met parameters were obtained from  
rawinsondes launched at "O" Camp.  The rawinsondes were launched two or     
more times each day.  This system was manufactured by the VIZ Corporation.  
The winds were measured by an Omega navigation tracking system on each      
rawinsonde.                                                                 
                                                                            
     The accuracy of the temperature and dewpoint temperature was 0.2       
degree C and 1.0 degree C respectively, while height was accurate to 30 m.  
Vector wind speed was usually accurate to 1.0 m/s, although in shear        
regions and near the surface errors may increase to 2.0 m/s.  Sometimes,    
the Omega tracking system had problems and errors were extreme.  These bad  
periods have not been removed from the data and can be identified by spikes 
or false jets in the sounding data.  A comparison of data obtained from two 
profiles made within an hour confirmed the above accuracy estimates.        
However, the reader should be cautioned that rawinsonde measurements are    
instantaneous and do not necessarily represent the average conditions,      
particularly if strong secondary circulations are present.                  
                                                                            
6.5  Instrumentation and Data Accuracy - CEAREX - "A" Camp                  
                                                                            
6.5.1  Surface Measurements - "A" Camp                                      
                                                                            
     Wind speed, wind direction, temperature, humidity and pressure were    
obtained from a Coastal Climate WeatherPak meteorological station (met      
station) and recorded on Hewlett-Packard 200 series computers.  The data    
were averaged over ten-minute periods.  The winds were measured at a height 
of 2.82 m above the ice surface.  Temperature, humidity, and pressure were  
measured at 2.24 m.  The temperature was accurate to 0.5 degree C; relative 
humidity, 8.0%; wind speed, 0.2 m/s; wind direction, 5.0 degrees; and       
pressure, 2.0 mb.  The pressure data show some high frequency fluctuations  
which are not believed to be real.                                          
                                                                            
     Important Note:  It was recently discovered that the humidity          
measurements from the Coastal Climate WeatherPak meteorological stations    
are highly suspect during cold conditions.  Therefore, consider all the     
humidity values in this file to be suspect when the air temperature is      
below -10 degrees C.  Contact Peter Guest (address in section 9) for        
details.  The upper-air humidities are not affected.                        
                                                                            
     The "A" Camp data were obtained entirely from the met station and      
contain no gaps larger than one-half hour.  No editing of the data was      
needed and the above accuracies and heights apply throughout the            
measurement period.                                                         
                                                                            
6.5.2  Upper-Air Measurements - "A" Camp                                    
                                                                            
     There were no upper-air measurements taken at "A" Camp.                
                                                                            
7.  Acknowledgements                                                        
                                                                            
     Unless otherwise noted, the data were collected and processed by       
members of the Environmental Physics Group, Department of Meteorology,      
Naval Postgraduate School (NPS).  Other directly-contributing individuals   
from other institutions are mentioned or referenced in the documentation.   
This data compilation would not have been possible without the effort of    
many other unmentioned individuals who were involved in planning, logistics,
data collection, data analyses and all the other tasks required to obtain   
data in the Arctic.                                                         
                                                                            
     The creation of this combined Arctic meteorological data base for      
the CD-ROM was supported by the Office of Naval Research Arctic Program     
(T. Curtin).  The Direct Research Funding Program at the Naval Postgraduate 
School and the Naval Oceanographic and Atmospheric Research Laboratory      
supported the NPS scientific effort that acquired much of the data.         
                                                                            
8.  References                                                              
                                                                            
Frederickson, P.A. (1991) CEAREX/HAAKON MOSBY Meteorology Atlas.  
     Technical Note 82, Naval Oceanographic and Atmospheric Research Laboratory, 62 pp.       
                                                                            
Guest, P.S. and K.L. Davidson (1989) CEAREX "O" and "A" Camp Meteorology    
     Atlas. Naval Postgraduate School, NPS-63-89-007, 64 pp.                
                                                                            
Guest, P.S. and K.L. Davidson (1988) MIZEX 87 Meteorology Atlas. Naval      
     Postgraduate School, NPS-63-88-004, 140 pp.                            
                                                                            
Lackmann, G.M., P.S. Guest, K.L. Davidson, R.J. Lind and J. Gonzales (1989) 
     CEAREX/POLARBJOERN Meteorology Atlas. Naval Postgraduate School,       
     NPS-63-89-005, 545 pp.                                                 
                                                                            
Lindsay, R.W. (1986) MIZEX 84 Six Hourly Radiosondes:  POLAR QUEEN, 
     POLARSTERN, HAAKON MOSBY, VALDIVIA. Polar Science Center, University 
     of Washington, Technical Report, 240 pp.                   
                                                                            
Lindsay, R.W. (1985) MIZEX 84 Integrated Surface Meteorological Data Set and
     Meteorological Atlas, 2nd ed. Polar Science Center, University of      
     Washington, Technical Report, 240 pp.                                  
                                                                            
Lindsay, R.W (1984) Radiosonde Observations from the POLARBJORN, MIZEX 83.  
     Polar Science Center, University of Washington. Technical Report, 
     280 pp.
                                                                         
9. Contact Information                                                    
                                                                          
     Peter Guest                                                          
     Naval Postgraduate School                                            
     Department of Meteorology, Code MR/Gs                                
     Monterey, CA   93943-5000 USA                                        
     Phone: 408-646-2451                                                  
     Telemail: K.DAVIDSON/Omnet                                           
                                                                          
February 1991 (revised March 1991)