Table 5 Comparison of surface elevations by Seasat and optical survey along EGIG line

Surface elevation maps of the southern half of the Greenland subcontinent are produced from radar altimeter data acquired by the Seasat satellite. A summary of the processing procedure and examples of return waveform data are given. The elevation data are used to generate a regular grid which is then computer contoured to provide an elevation contour map. Ancillary maps show the statistical quality of the elevation data and various characteristics of the surface. The elevation map is used to define ice flow directions and delineate the major drainage basins. Regular maps of the Jakobshavns Glacier drainage basin and the ice divide in the vicinity of Crete Station are presented. Altimeter derived elevations are compared with elevations measured both by satellite geoceivers and optical surveying.

Properties of seawater and particulate matter from a FRRF instrument, operating in a flow-through mode on the continuous surface water sampling system during the Tara Oceans expedition 2009-2013

The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. The present data set provides continuous measurements made with a FRRF instrument, operating in a flow-through mode during the 2009-2012 part of the expedition. It operates by exciting chlorophyll fluorescence using a series of short flashes of controlled energy and time intervals (Kolber et al, 1998). The fluorescence transients produced by this excitation signal were analysed in real-time to provide estimates of abundance of photosynthetic pigments, the photosynthetic yields (Fv/Fm), the functional absorption cross section (a proxy for efficiency of photosynthetic energy acquisition), the kinetics of photosynthetic electron transport between Photosystem II and Photosystem I, and the size of the PQ pool. These parameters were measured at excitation wavelength of 445 nm, 470nm, 505 nm, and 535 nm, allowing to assess the presence and the photosynthetic performance of different phytoplankton taxa based on the spectral composition of their light harvesting pigments. The FRRF-derived photosynthetic characteristics were used to calculate the initial slope, the half saturation, and the maximum level of Photosynthesis vs Irradiance relationship. FRRF data were acquired continuously, at 1-minute time intervals.