1 NODC Quality Control : Automatic Checks - reveal systematic errors in incoming data and metadata - eliminate most non-representative data from consideration Eliminates ~6% of temperature data from Consideration (>800,000 profiles) Checks include: Range check Spike check Density inversion Speed check Standard deviation Red – Unflagged Black – Flagged

31 distinct regions with ocean variable ranges at standard depths, includes separate ranges for coastal regions 177,000 temperature profiles affected (1.5%) Min/Max Range Checks

Inversion and Large Gradient Checks For Temperature: Inversion ≤ -0.3°C/meter Gradient ≥ 0.7°C/meter MBT with large inversion °Celsius Depth (meters) Inversions present In 276,000 temperature Profiles (2% of profiles) Large positive gradients Present in 534,000 Temperature profiles (4% of profiles)

Density inversions – when local stability with respects to density less than zero Check applied at observed levels, but not used to exclude data from interpolation to standard levels Check applied at standard levels. Interpolation procedure can introduce inversions. Two or more density inversions at same station and whole temperature and salinity profiles are marked and not used to calculate climatologies. 214,00 temperature and salinity casts not used due to two or more density inversions on standard levels (1.6% of all temperature profiles, 3.7% of all salinity profiles) Density inversion check

Standard Deviation Checks check is on standard levels 5° means and standard deviations used values flagged if they exceed 3 to 5 times standard deviations from mean - 3 times for upper 50 meters for coastal data - 4 times for near coastal and near bottom data - 5 times for all other data profile not used for climatologies if it has 2 or more standard deviation flags separate checks for annual, seasonal, monthly time periods 367,000 temperature profiles flagged with more than 2 annual mean/standard deviation failures (3% of total profiles) - 233,000 salinity profiles flagged (4% of total)

May – August 1976 Cruise of Russian Ship Priboy (Russian Far East Scientific Research Institute)

Blue Dots = Phosphate data from Priboy cruise, 2839 stations. Red Dots = other Phosphate in representative 5° square in North Pacific, 5455 stations Red Solid Line = Mean phospate values at standard depths for same 5° square Red Dotted Line = ±3 to 5 standard deviations for 5° square Green Line= Mean Priboy cruise phosphate with correction applied Estimated fix of data: Correct value = (3.189 X initial value) Problem is due to difference in Molecular weight conventionally Used by Russians, Americans

Flag values: 0-9 Flag value: 2 Flag values: 3-9 Depth: 0-50 m Depth: m Depth: m Years: Month: Jan - Mar Courtesy Igor Smolyar

Region: 73º-75º N, 10º-45º E , Jan-Apr Temperature data 0-20 m All measurements Flagged values: Standard Deviation outliers Fuzzy logic method Temperature (°C) Courtesy Igor Smolyar

# CRUZTRACK REPORT FORM: # Statn Date Time Latitde Longitde Dist / TLS = Speed * UniqStat Access# Ship MP # O 1 2/ 7/ / 7/ / 7/ / 7/ / 7/ / 8/ * Cruise Speed/ Cruise Track Check

“Bullseyes” in December Salinity Climatology at Surface Before cleanup After cleanup Problems along 180 longitude caused by December, 1979 Russian cruise. An archiving error involving a computer at the Russian National Oceanographic Data Center caused decrease In salinity values. We are able to recover original values for these data Thank you – Questions?