Winter lovers: engajamento e participação no universo de game of thrones da internet

The formation of groups acquired new features with the arrival of the internet. The links before straitened between family, work groups and close friends today reach long distances through online communities. These communities represent groups that have affinities and common interests, and use the community space to discuss these. Examples of these communities are those related to franchise Game of Thrones, a literary phenomenon that has expanded by various media, including the social, television, and communities. This report aims to present the work steps and the theoretical reflection, necessary for the achievement of a final product in file format, which aimed to measure the engagement and participation of GOT fans on the Internet, especially in two Facebook GOT communities during the fifth season of the series aired on HBO.

Viral, bacterial and ciliate abundance and viral-bacterial diversity in mesocosm experiments, 2007-2008, Kongsfjorden

Two mesocosm experiments, PAME-I and PAME-II were conducted in 2007 and 2008 to investigate fate of organic carbon in the arctic microbial food web. Mesocosms were nutrient fertilized initially to induce phytoplankton bloom development. In PAME-I eight units (each 700 L) formed two four point gradients of additional DOC in form of glucose (0, 0.5, 1 and 3 times Redfield ratio in terms of carbon relative to the nitrogen and phosphorus additions) (Fig. 1). All the eight units also got a daily dose of NH4+ and PO4**3- in Redfield ratio. Two gradients were set up, one with silicate addition, performed in the Arctic location Ny Ålesund, Svalbard, have previously been reported to give different food-web level responses to similar nutrient perturbations. In PAME-II all ten units (each 900 L) formed two four point gradients of additional DOC in form of glucose (0, 0.5, 1, 2 and 3 times Redfield ratio in terms of carbon relative to nitrogen and phosphorus additions). The two gradients in glucose were kept silicate replete. NH4+ was used as the DIN source in one gradient (units 1 to 5) and NO3- in the other (units 6-9). All units got a daily dose of PO4**3- in Redfield ratio. Prokaryotes and viruses were measured by flow cytometry, while ciliate abundances were counted using a Flow Cam. Viral and bacterial diversity was measured by PFGE and DGGE, respectively. In PAME-II the abundance of ciliates was lower than in PAME-I, presumably caused by higher copepod grazing. The abundances of prokaryotes and viruses were also lower in PAME-II compared to PAME-I. Further, less diversity was detected in the viral community (FCM and PFGE) in PAME-II, and no response was observed in the bacterial community structure due to addition of organic carbon.

Surface wind stress modeled for the Panama Seaway with the Community Climate System Model 3

The early Pliocene warm phase was characterized by high sea surface temperatures and a deep thermocline in the eastern equatorial Pacific. A new hypothesis suggests that the progressive closure of the Panamanian seaway contributed substantially to the termination of this zonally symmetric state in the equatorial Pacific. According to this hypothesis, intensification of the Atlantic meridional overturning circulation (AMOC) - induced by the closure of the gateway - was the principal cause of equatorial Pacific thermocline shoaling during the Pliocene. In this study, twelve Panama seaway sensitivity experiments from eight ocean/climate models of different complexity are analyzed to examine the effect of an open gateway on AMOC strength and thermocline depth. All models show an eastward Panamanian net throughflow, leading to a reduction in AMOC strength compared to the corresponding closed-Panama case. In those models that do not include a dynamic atmosphere, deepening of the equatorial Pacific thermocline appears to scale almost linearly with the throughflow-induced reduction in AMOC strength. Models with dynamic atmosphere do not follow this simple relation. There are indications that in four out of five models equatorial wind-stress anomalies amplify the tropical Pacific thermocline deepening. In summary, the models provide strong support for the hypothesized relationship between Panama closure and equatorial Pacific thermocline shoaling.

Near real time surface ocean velocity, Tyrrhenian Sea and Ligurian Sea in September 2016

The data set consists of maps of total velocity of the surface current in the North-Western Tyrrhenian Sea and Ligurian Sea averaged over a time interval of 1 hour around the cardinal hour. Surface ocean velocities estimated by HF Radar are representative of the upper 0.3-2.5 meters of the ocean. Total velocities are derived using least square fit that maps radial velocities measured from individual sites onto a cartesian grid. The final product is a map of the horizontal components of the ocean currents on a regular grid in the area of overlap of two or more radar stations.

SeaWiFS (version R2010.0) Monthly Global 9 km Microplankton Fraction, links to NetCDF files

Phytoplankton cell size is important to biogeochemical and food web processes. The goal of this study is to estimate phytoplankton cell size distribution from satellite imagery of spectral remote sensing reflectance (Rrs(lambda)). Previous studies have indicated phytoplankton size classes have distinctive absorption spectra despite the physiological and taxonomic variability within an assemblage. For this study, the chlorophyll specific absorption spectra for phytoplankton size class extremes, pico- and microphytoplankton, are weighted by the percent microplankton (Sfm) and are the basis of phytoplankton size retrieval from SeaWiFS imagery. Satellite retrievals of Sfm are done through implementation of a forward optical model look-up table (LUT) that incorporates the range of absorption and scattering variability due to phytoplankton size, chlorophyll concentration ([Chl]) and dissolved and detrital matter (acdm(443)) in the global ocean from which Rrs(lambda) is calculated by the radiative transfer software, Hydrolight. The Hydrolight modeled Rrs(lambda) options for a given combination of [Chl] and acdm(443) within the LUT vary only due to Sfm. For a given pixel, the LUT search space was limited by satellite imagery of [Chl] and acdm(443). Within the narrowed search space, SeaWiFS Rrs(lambda) was matched with the closest LUT Rrs(lambda) option and the associated Sfm was assigned. Thresholds at which changes in Rrs(lambda) due to Sfm could be discerned were established in terms of [Chl] and acdm(443). In situ high-precision liquid chromatography-derived estimates of cell size are used in conjunction with matched daily satellite estimates of Sfm for validation and agree well. A single month is displayed as an example of the Sfm retrieval.

Melt climatology estimates for small to giant Antarctic icebergs, links to NetCDF files

We present four melt climatology estimates based on a simulation of Antarctic iceberg drift and melting that includes small, medium-sized, and giant tabular icebergs with a realistic size distribution. Drift and meltdown is simulated using vertical profiles of ocean currents, temperature, and salinity, which goes beyond the present standard in iceberg modeling. The climatology estimates based on simulations of small (SMA), 'small-to-medium'-sized (MED12 & MED123), and small-to-giant icebergs (ALL) exhibit differential characteristics: successive inclusion of larger icebergs leads to a reduced seasonality of iceberg melt and a shift of the mass input to the area north of 58°S, while less melt water is released into the coastal areas. This highlights the necessity to account for larger and giant icebergs in order to obtain accurate melt climatologies. The four monthly melt climatologies [mm/day] are available as netCDF files with 1°x1° spatial resolution and can be used, e.g., for sensitivity studies with uncoupled sea ice-ocean models, or as spatio-temporal templates for the redistribution of land ice from the Antarctic ice sheet over the Southern Ocean in climate models.

Total sediment thickness grid of the Southern Pacific Ocean off West Antarctica, links to NetCDF files

Paleotopographic models of the West Antarctic margin, which are essential for robust simulations of paleoclimate scenarios, lack information on sediment thickness and geodynamic conditions, resulting in large uncertainties. A new total sediment thickness grid spanning the Ross Sea-Amundsen Sea-Bellingshausen Sea basins is presented and is based on all the available seismic reflection, borehole, and gravity modeling data offshore West Antarctica. This grid was combined with NGDC's global 5 arc minute grid of ocean sediment thickness (Whittaker et al., 2013, doi:10.1002/ggge.20181) and extends the NGDC grid further to the south. Sediment thickness along the West Antarctic margin tends to be 3-4 km larger than previously assumed. The sediment volume in the Bellingshausen, Amundsen, and Ross Sea basins amounts to 3.61, 3.58, and 2.78 million km³, respectively. The residual basement topography of the South Pacific has been revised and the new data show an asymmetric trend over the Pacific-Antarctic Ridge. Values are anomalously high south of the spreading ridge and in the Ross Sea area, where the topography seems to be affected by persistent mantle processes. In contrast, the basement topography offshore Marie Byrd Land cannot be attributed to dynamic topography, but rather to crustal thickening due to intraplate volcanism. Present-day dynamic topography models disagree with the presented revised basement topography of the South Pacific, rendering paleotopographic reconstructions with such a limited dataset still fairly uncertain.

Pre-glacial to glacial sediment thickness grids for the Southern Pacific Margin of West Antarctica, NetCDF files

Circum-Antarctic sediment thickness grids provide constraints for basin evolution and paleotopographic reconstructions, which are important for paleo-ice sheet formation histories. By compiling old and new seismic data, we identify sequences representing pre-glacial, transitional and full glacial deposition processes along the Pacific margin of West Antarctica. The pre-glacial sediment grid depicts 1.3 to 4.0 km thick depocenters, relatively evenly distributed along the margin. The depocenters change markedly in the transitional phase at, or after, the Eocene/Oligocene boundary, when the first major ice sheets reached the shelf. Full glacial sequences, starting in the middle Miocene, indicate new depocenter formation North of the Amundsen Sea Embayment and localized eastward shifts in the Bellingshausen Sea and Antarctic Peninsula basins. Using present-day drainage paths and source areas on the continent, our calculations indicate an estimated observed total sedimentary volume of ~10 x 10**6 km**3 was eroded from West Antarctica since the separation of New Zealand in the Late Cretaceous. Of this 4.9 x 10**6 km**3 predates the onset of glaciation and need to be considered for a paleotopography reconstruction of 34 Ma. Whereas 5.1 x 10**6 km**3 postdate the onset of glaciation, of which 2.5 x 10**6 km**3 were deposited in post mid-Miocene full glacial conditions.

Sea ice thickness distribution (ITD) Model for the Arctic, links to NetCDF files

Sea ice models contain many different parameterizations of which one of the most commonly used is a subgrid-scale ice thickness distribution (ITD). The effect of this model component and the associated ice strength formulation on the reproduction of observed Arctic sea ice is assessed. To this end the model's performance in reproducing satellite observations of sea ice concentration, thickness and drift is evaluated. For an unbiased comparison, different model configurations with and without an ITD are tuned with an automated parameter optimization. The original combination of ITD and ice strength parameterization does not lead to better results than a simple single category model. Yet changing to a simpler ice strength formulation, which depends linearly on the mean ice thickness across all thickness categories, allows to clearly improve the model-data misfit when using an ITD. In the original formulation, the ice strength depends strongly on the number of thickness categories, so that introducing more categories can lead to thicker albeit weaker ice on average.

Seafloor spreading magnetic anomaly isochron map compilation for the Weddell Sea and Scotia Sea

The deep sea sedimentary record is an archive of the pre-glacial to glacial development of Antarctica and changes in climate, tectonics and ocean circulation. Identification of the pre-glacial, transitional and full glacial components in the sedimentary record is necessary for ice sheet reconstruction and to build circum-Antarctic sediment thickness grids for past topography and bathymetry reconstructions, which constrain paleoclimate models. A ~3300 km long Weddell Sea to Scotia Sea transect consisting of multichannel seismic reflection data from various organisations, were used to interpret new horizons to define the initial basin-wide seismostratigraphy and to identify the pre-glacial to glacial components. We mapped seven main units of which three are in the inferred Cretaceous-Paleocene pre-glacial regime, one in the Eocene-Oligocene transitional regime and three units in the Miocene-Pleistocene full glacial climate regime. Sparse borehole data from ODP leg 113 and SHALDRIL constrain the ages of the upper three units. Compiled seafloor spreading magnetic anomalies constrain the basement ages and the hypothetical age model. In many cases, the new horizons and stratigraphy contradict the interpretations in local studies. Each seismic sedimentary unit and its associated base horizon are continuous and traceable for the entire transect length, but reflect a lateral change in age whilst representing the same deposition process. The up to 1240 m thick pre-glacial seismic units form a mound in the central Weddell Sea basin and, in conjunction with the eroded flank geometry, support the interpretation of a Cretaceous proto-Weddell Gyre. The base reflector of the transitional seismic unit, which marks the initial ice sheet advances to the outer shelf, has a lateral model age of 26.6-15.5 Ma from southeast to northwest. The Pliocene-Pleistocene glacial deposits reveals lower sedimentations rates, indicating a reduced sediment supply. Sedimentation rates for the pre-glacial, transitional and full glacial components are highest around the Antarctic Peninsula, indicating higher erosion and sediment supply of a younger basement. We interpret an Eocene East Antarctic Ice Sheet expansion, Oligocene grounding of the West Antarctic Ice Sheet and Early Miocene grounding of the Antarctic Peninsula Ice Sheet.

Holocene experiment with coupled atmosphere-ocean-model ECHAM5/MPI-OM

Changes in the Earth's orbit lead to changes in the seasonal and meridional distribution of insolation. We quantify the influence of orbitally induced changes on the seasonal temperature cycle in a transient simulation of the last 6000 years - from the mid-Holocene to today - using a coupled atmosphere-ocean general circulation model (ECHAM5/MPI-OM) including a land surface model (JSBACH). The seasonal temperature cycle responds directly to the insolation changes almost everywhere. In the Northern Hemisphere, its amplitude decreases according to an increase in winter insolation and a decrease in summer insolation. In the Southern Hemisphere, the opposite is true. Over the Arctic Ocean, decreasing summer insolation leads to an increase in sea-ice cover. The insulating effect of sea ice between the ocean and the atmosphere leads to decreasing heat flux and favors more "continental" conditions over the Arctic Ocean in winter, resulting in strongly decreasing temperatures. Consequently, there are two competing effects: the direct response to insolation changes and a sea-ice insulation effect. The sea-ice insulation effect is stronger, and thus an increase in the amplitude of the seasonal temperature cycle over the Arctic Ocean occurs. This increase is strongest over the Barents Shelf and influences the temperature response over northern Europe. We compare our modeled seasonal temperatures over Europe to paleo reconstructions. We find better agreements in winter temperatures than in summer temperatures and better agreements in northern Europe than in southern Europe, since the model does not reproduce the southern European Holocene summer cooling inferred from the paleo reconstructions. The temperature reconstructions for northern Europe support the notion of the influence of the sea-ice insulation effect on the evolution of the seasonal temperature cycle.

Antarctic ice sheet topography, cavity geometry, and global bathymetry (RTopo 1.0.5-beta)

Sub-ice shelf circulation and freezing/melting rates in ocean general circulation models depend critically on an accurate and consistent representation of cavity geometry. Existing global or pan-Antarctic data sets have turned out to contain various inconsistencies and inaccuracies. The goal of this work is to compile independent regional fields into a global data set. We use the S-2004 global 1-minute bathymetry as the backbone and add an improved version of the BEDMAP topography for an area that roughly coincides with the Antarctic continental shelf. Locations of the merging line have been carefully adjusted in order to get the best out of each data set. High-resolution gridded data for upper and lower ice surface topography and cavity geometry of the Amery, Fimbul, Filchner-Ronne, Larsen C and George VI Ice Shelves, and for Pine Island Glacier have been carefully merged into the ambient ice and ocean topographies. Multibeam survey data for bathymetry in the former Larsen B cavity and the southeastern Bellingshausen Sea have been obtained from the data centers of Alfred Wegener Institute (AWI), British Antarctic Survey (BAS) and Lamont-Doherty Earth Observatory (LDEO), gridded, and again carefully merged into the existing bathymetry map. The global 1-minute dataset (RTopo-1 Version 1.0.5) has been split into two netCDF files. The first contains digital maps for global bedrock topography, ice bottom topography, and surface elevation. The second contains the auxiliary maps for data sources and the surface type mask. A regional subset that covers all variables for the region south of 50 deg S is also available in netCDF format. Datasets for the locations of grounding and coast lines are provided in ASCII format.

Holocene precipitation change in different monsoon sub-regions (time-slices and transient data) simulated by different global climate models, with links to model results

The recently proposed global monsoon hypothesis interprets monsoon systems as part of one global-scale atmospheric overturning circulation, implying a connection between the regional monsoon systems and an in-phase behaviour of all northern hemispheric monsoons on annual timescales (Trenberth et al., 2000). Whether this concept can be applied to past climates and variability on longer timescales is still under debate, because the monsoon systems exhibit different regional characteristics such as different seasonality (i.e. onset, peak, and withdrawal). To investigate the interconnection of different monsoon systems during the pre-industrial Holocene, five transient global climate model simulations have been analysed with respect to the rainfall trend and variability in different sub-domains of the Afro-Asian monsoon region. Our analysis suggests that on millennial timescales with varying orbital forcing, the monsoons do not behave as a tightly connected global system. According to the models, the Indian and North African monsoons are coupled, showing similar rainfall trend and moderate correlation in rainfall variability in all models. The East Asian monsoon changes independently during the Holocene. The dissimilarities in the seasonality of the monsoon sub-systems lead to a stronger response of the North African and Indian monsoon systems to the Holocene insolation forcing than of the East Asian monsoon and affect the seasonal distribution of Holocene rainfall variations. Within the Indian and North African monsoon domain, precipitation solely changes during the summer months, showing a decreasing Holocene precipitation trend. In the East Asian monsoon region, the precipitation signal is determined by an increasing precipitation trend during spring and a decreasing precipitation change during summer, partly balancing each other. A synthesis of reconstructions and the model results do not reveal an impact of the different seasonality on the timing of the Holocene rainfall optimum in the different sub-monsoon systems. They rather indicate locally inhomogeneous rainfall changes and show, that single palaeo-records should not be used to characterise the rainfall change and monsoon evolution for entire monsoon sub-systems.