Questions: Mountain systems have high abiotic heterogeneity over local spatial scales, offering natural experiments for examining plant species invasions. We ask whether functional groupings explain non-native species spread into native vegetation and up elevation gradients.We examine whether non-native species distribution patterns are related to environmental variables after controlling for elevation...
The target strengths and swimbladder morphology of six snapper species were investigated using broadband sonar, x rays, and swimbladder casts. Backscatter data were obtained using a frequency-modulated sweep ~60–200 kHz! and a broadband, dolphinlike click ~peak frequency 120 kHz! from live fish, mounted and rotated around each of their three...
In 2002, oxygen isotope ratios of water (H2
18O/H2
16O), dissolved barium, and salinity were
measured in surface waters around northern North America to identify freshwater sources and to
provide a large-scale background for interpretation of regional inputs and processes. Oxygen isotope
ratios showed that precipitation, river runoff, and sea...
We examined the characteristics of biological patches at four different locations to assess the relationship of patch vertical scale, amplitude, and persistence. In contrast to patches of larger animals, we found that the majority of coherent aggregations of plankton at each site were vertically compressed, with most smaller than 5m...
The semidiurnal mode-1 internal tide receives 0.1-0.3 TW from the surface tide and is capable of propagating across ocean basins. The ultimate fate of mode-1 energy after long-distance propagation is poorly constrained by existing observations and numerical simulations. Here, global results from a two-dimensional semi-analytical model indicate that topographic scattering...
Interannual variation in precipitation totals is a critical factor governing the year-to-year availability of water resources, yet the connection between interannual precipitation variability and underlying event- and season-scale precipitation variability remains unclear. In this study, tropical and midlatitude precipitation characteristics derived from extensive station records and high-frequency satellite observations were...
Upper ocean hydrography in the central Arctic Ocean
has relaxed since 2000 to near-climatological conditions
that pertained before the dramatic changes of the 1990s. The
behavior of the anomalies of temperature and salinity in the
central Arctic Ocean follow a first-order linear response to
the AO with time constant of...
Abstract: Tide-topography interactions dominate the transfer of tidal energy from large to small scales. At present, it is poorly understood how low-mode internal tides reflect and scatter along the continental margins. Here, the coupling equations for linear tides model (CELT) are derived to determine the independent modal solutions to Laplace's...
• Premise of the study: Colonists of even the most inhospitable environments, lichens are present in all terrestrial ecosystems.
Because of their ecological versatility and ubiquity, they have been considered excellent candidates for early colonizers of terrestrial
environments. Despite such predictions, good preservation potential, and the extant diversity of lichenized...
Dissolved barium (Ba) was measured along transects across Fram and Denmark Straits as part of the 1998 ARK-XIV/2 Polarstern expedition. Results are combined with other available tracer observations to analyze water mass composition at Fram Strait. A combination of Pacific water and Eurasian river runoff dominated (>80% and >10% of...