GOAL hydrographic gridded product for the Northern Antarctic Peninsula

 

Description: The Northern Antarctic Peninsula (NAP) climatology version 1 (NAPv1.0) was built by optimally interpolate hydrographic data sets from the CTD, MEOP and Argo floats profiles sampled in the NAP and adjacent regions during the period of 1990-2019. The database consists of data from the World Ocean Database, Pangaea, Hutchinson et al. (2020), Brazilian High Latitude Oceanography Group (GOAL), Marine Mammals Exploring the Oceans Pole to Pole consortium (MEOP), and Argo floats. The climatology has outputs for summer (Jan-Mar), autumn (Apr-Jun), winter (Jul-Sep) and spring (Oct-Dec). The profiles were first linearly interpolated onto 90 depth levels, and then optimally interpolated in space using a grid of ~10 km resolution. The grid spacing is 0.09˚ along latitudes and 0.2˚ along longitudes (i.e., 0.09˚ latitude x 0.09˚/cos(63˚S) longitude, where 63˚S is the mean latitude of our domain). A series of tests were made to find the appropriate smoothing lengthscale and the a priori relative error in order to find a balance between smoothness and feature representativeness. The final smoothing lengthscale (i.e. the radius of influence of the interpolation) chosen was 1˚ in latitude and longitude, and the a priori relative error allowed was set to 0.2 for the objective interpolation algorithm. The same constants were set for all depth levels and all variables. The regions where the mapping relative error was higher than 0.5 were excluded. The NAPv1.0 climatology can be used for several applications, including input data for ocean and climate models initialization/assessment and ocean reanalysis evaluation, as well as to produce and reconstruct biogeochemical properties. The NAPv1.0 climatology represents the ocean mean-state for the NAP for the end of the 20th and early 21st-century.

 

Authors: Dotto, T. S., Kerr, R., Mata, M. M. and Garcia, C. A. E.

 

How to cite: Dotto, T. S., Mata, M. M., Kerr, R., and Garcia, C. A. E.: A novel hydrographic gridded data set for the Northern Antarctic Peninsula, Earth Syst. Sci. Data Discuss. [preprint], https://doi.org/10.5194/essd-2020-244, in review, 2020. 

 

Data files description: The file contains the 4D gridded variables in situ temperature (TMP; ˚C), practical salinity (SAL), dissolved oxygen (OXY; mL L-1) and their respective relative error matrices. Depth levels (in metres) and the 2D gridded coordinates latitude and longitude are also included in the file. The 4th dimension is the season: summer, autumn, winter and spring. Missing values corresponding to relative errors > 0.5 and land mask are marked as not a number (NaN).

 

Data files download:  NAPv1p0.zip