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Information on text files of data for Ronne Polynya flights F49, F54, F57.

Data files are organised for each flight leg, i.e. F49L2, F54L1, F54L2, F57L1.

Each data point is the average over a period of 140 seconds.

All data for L2s, i.e. legs where plane was flying towards ice shelf, are
flipped around so that 0 km fetch is the edge of the ice shelf.

Rejected quality controlled points NaN

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B_sfc = Surface buoyancy flux (m^2 s^{-3})
B_sfc_winter = estimated buoyancy flux assuming wintertime heat budget, i.e.
shortwave is zero.

Bowen = Bowen ratio (sensible heat/latent heat)

CDN10 = neutral stability 10m drag coefficient
CHN10 = neutral stability 10m heat transfer coefficient

Dewpoint_cm = cooled mirror dewpoint (degrees C)
Dewpoint_hc = Humicap dewpoint (degrees C)

GPS_alt = altitude measured using GPS (m)

L = Monin-Obukhov length

LWD = downwelling longwave (W m^{-2})
LWU = upwelling longwave (W m^{-2})

P = pressure at measurement height (hPa (mb) )

QC = quality control, i.e. which points were rejected from turbulence analysis,
given as the indices of rejected points

Q_L_Bowen = Latent heat flux calculated using sensible heat flux and
mean Bowen ratio from all flights (3.8) (W m^{-2})

Q_L_bulk = Latent heat flux calculated using bulk formula, assuming CHr=CEr
(W m^{-2})

Q_S = eddy covariance sensible heat flux (W m^{-2})

Q_rad = net radiative heat flux (W m^{-2})

Q_tot = total surface energy budget (=Q_rad + Q_S + Q_L) (W m^{-2})

Q_tot_winter = total wintertime surface energy budget (i.e. assuming SW
component of Q_rad is zero) (W m^{-2})

SWD = downwelling shortwave (corrected for angle of plane) (W m^{-2})
SWU = upwelling shortwave (NOT corrected for field of view covered by skis
(W m^{-2}))

T_air = air temperature (degrees C) from Rosemount

T_sfc = surface temperature (degrees C) from IRT (infrared radiation thermometer), calibrated assuming highest
measured temperature over polynya corresponds to -1.9 degrees C

V_i = volume of ice produced per year (in m) with offshore polynya fetch, 
assuming rectangular polynya with an along-shore width of 300 km, i.e. for 
area of each strip of fetch within the rectangle.

albedo_corrected = surface SW albedo, using SWD corrected for angle of plane

ave_period = averaging period for the data, 140 seconds

fetch = offshore fetch (km), point is centre of fetch range for averaging 
period

fetch_QC = as above, but with NaN points for those removed after quality
control

flight = flight number

leg = leg number (1 is away from ice shelf, 2 is towards)

q_air = specific humidity of the air (g g^{-1})

q_sfc = specific humidity of the surface (g g^{-1})

rad_alt = altitude measured using radar altimeter (m)

rho = calculated air density (kg m^{-3})

tau = wind stress (N m^{-2})

theta_air = potential temperature, calculated with respect to surface (K)

time = time in hours (UTC). As L2s are flipped round, time is also running 
backwards for these flights.

u_star = friction velocity (m s^{-1})

wd = wind direction (degrees), where 0 degrees is South

ws = wind speed (m s^{-1})

z = mean measurement height (from rad_alt) (m)

z0 = roughness length (m)