ALBERT

Description: This sample collection presents a database that integrates surficial sediment samples collected and analysed for textural characterization within the frame of a series of research projects. A total of 4727 samples within the frame of 24 projects developed between 1996 and 2015 along the southern Atlantic coast of the Iberian Peninsula. The projects had different purposes, including fishing exploration, coastal dynamics investigation or monitoring of nourished beaches. The variety of the projects also explains the variety of environments that have been sampled and compiled within this database. The latter includes beaches (emerged to nearshore sediments), estuaries (bed surface sediments), lagoons (bed surface sediments from channels, inlets and inner beaches), and the adjacent continental shelf (from the nearshore area to 300 m depth). Data collection was performed by hand (at beaches and inlets) and using grab samplers (at the shelf). All collected samples were examined and analysed in order to determine their grain-size distribution. Due to the diversity of environments sampled and the subsequent variety of sediments, different methods were used to determine grain size properties. For those samples with grain sizes between sand and gravels, the distribution of size fractions was obtained through dry sieving at each 0.5 phi, except for CRIDA, EMERGE, SIRIA and SIMPATICO datasets which have been analysed at each phi. For those cases with grain sizes finer than sand (i.e. silt and clay fractions), the pipette or settling tube was used and the corresponding fractions analysed at each phi. The value *0.999 is given for "not recovered record".

Description: Ice rich Yedoma-dominated landscapes store considerable amounts of organic carbon (C) and nitrogen (N) and are vulnerable to degradation under climate warming. We investigate the C and N pools in two thermokarst-affected Yedoma landscapes - on Sobo-Sise Island and on Bykovsky Peninsula in the North of East Siberia. Soil cores up to three meters depth were collected along geomorphic gradients and analysed for organic C and N contents. A high vertical sampling density in the profiles allowed the calculation of C and N stocks for short soil column intervals and enhanced understanding of within-core parameter variability. Profile-level C and N stocks were scaled to the landscape level based on landform classifications from five-meter resolution, multispectral RapidEye satellite imagery. Mean landscape C and N storage in the first meter of soil for Sobo-Sise Island is estimated to be 20.2 kg C/m**-2 and 1.8 kg N/m**-2 and for Bykovsky Peninsula 25.9 kg C/m**-2 and 2.2 kg N/m**-2. Radiocarbon dating demonstrates the Holocene age of thermokarst basin deposits but also suggests the presence of thick Holocene aged cover layers which can reach up to two meters on top of intact Yedoma landforms. Reconstructed sedimentation rates of 0.10 mm/yr - 0.57 mm/yr suggest sustained mineral soil accumulation across all investigated landforms. Both Yedoma and thermokarst landforms are characterized by limited accumulation of organic soil layers (peat). We further estimate that an active layer deepening by about 100 cm will increase organic C availability in a seasonally thawed state in the two study areas by ~5.8 Tg (13.2 kg C/m**-2). Our study demonstrates the importance of increasing the number of C and N storage inventories in ice-rich Yedoma and thermokarst environments in order to account for high variability of permafrost and thermokarst environments in pan-permafrost soil C and N pool estimates.

Description: In Gobabeb, Namibia SWD, LWD and DIR are each measured redundant with two instruments of the same make (not in this data base). The differences between the pairs are used in the quality control. This is done manually by inspecting plots of half-day diurnal courses of the pairs and their differences. Values are removed mostly in the morning due to daily cleaning. Other reasons for larger differences are birds, insects, or people at the station. There are regular fog events varying in frequency over the year. Usually, the fog appears in the second half of the night and disappears a few hours after sunrise. The case temperatures of pyrgeometers practically never drop below dewpoint but there can be water deposition of the dome.

Description: In Gobabeb, Namibia SWD, LWD and DIR are each measured redundant with two instruments of the same make (not in this data base). The differences between the pairs are used in the quality control. This is done manually by inspecting plots of half-day diurnal courses of the pairs and their differences. Values are removed mostly in the morning due to daily cleaning. Other reasons for larger differences are birds, insects, or people at the station. There are regular fog events varying in frequency over the year. Usually, the fog appears in the second half of the night and disappears a few hours after sunrise. The case temperatures of pyrgeometers practically never drop below dewpoint but there can be water deposition of the dome.