Plate tectonics: When ancient continents collide

The geological record preserves scant evidence for early plate tectonics. Analysis of eclogites — metamorphic rocks formed in subduction zones — in the Trans-Hudson mountain belt suggests modern-style subduction may have operated 1,800 million years ago

Summary of results of January climate simulations with the GISS coarse-mesh model

The large scale climates generated by extended runs of the model are relatively independent of the initial atmospheric conditions, if the first few months of each simulation are discarded. The perpetual January simulations with a specified SST field produced excessive snow accumulation over the continents of the Northern Hemisphere. Mass exchanges between the cold (warm) continents and the warm (cold) adjacent oceans produced significant surface pressure changes over the oceans as well as over the land. The effect of terrain and terrain elevation on the amount of precipitation was examined. The evaporation of continental moisture was calculated to cause large increases in precipitation over the continents

Here be Dragons: The Unexplored Continents of the CMSSM

The Higgs boson mass and the abundance of dark matter constrain the CMSSM/mSUGRA supersymmetry breaking inputs. A complete map of the CMSSM that is consistent with these two measured quantities is provided. Various "continents," consisting of non-excluded models, can be organized by their dark matter dynamics. The following mechanisms manifest: well-tempering, resonant pseudo-scalar Higgs annihilation, neutralino/stau coannihilations and neutralino/stop coannihilations. Benchmark models are chosen in order to characterize the viable regions. The expected visible signals of each are described, demonstrating a wide range of predictions for the 13 TeV LHC and a high degree of complementarity between dark matter and collider experiments. The parameter space spans a finite volume, which can be probed in its entirety with experiments currently under consideration.Comment: 58 pages + references, 21 figures, data files included on arXiv; v2: references added, minor changes; v3: journal version, minor change

Is Helicoverpa armigera (Lepidoptera: Noctuidae) in Brazil? First detailed molecular detection report

The cotton bollworm, Helicoverpa armigera, is a quarantine agricultural pest for the American continents. It is thought to have invaded the American continents and led the founding of current H. zea populations in the American continents ~1.5 million years ago. This relatively recent divergence is evident via hybridisation under laboratory conditions. Despite periodic incursions of H. armigera into North America, this pest species is not believed to have successfully established significant populations in the New World. For the first time, we provide molecular evidence via mitochondrial DNA (mtDNA), cytochrome oxidase I (COI) and cytochrome b (Cyt b) partial gene sequences the successful recent incursion of H. armigera into the New World, with populations from the state of Mato Grosso (central-eastern and southern regions) in Brazil, likely to have taken place post 2006. The mtDNA haplotypes detected in the Brazilian H. armigera individuals are common throughout the Old World, thus precluding identification of Old World origins of the founder populations. Combining the two partial mtDNA gene sequences we showed that at least two matrilines were present in Brazil, while the inclusion of three nuclear DNA Exon-Primed Intron-Crossing (EPIC) markers identified a further two possible matrilines. Based upon five genetic markers, the Brazilian H. armigera from Mato Grosso likely originated from at least four maternal lineages. (Résumé d'auteur

Intercontinental antenna arraying by symbol stream combining at ICE Giacobini-Zinner encounter

Deep space tracking stations on different continents were arrayed during the encounter of the International Cometary Explorer (ICE) spacecraft with the comet Giacobini-Zinner during September 9 through 12, 1985. This is the first time that telemetry signals received on different continents have been combined to enhance signal to noise ratio. The arraying was done in non-real time using the method of symbol stream combining. The improvement in signal to noise ratio was typically 2 dB over the stronger of the two stations in each array

Early recognition by Ball and Hooker in 1878 of plant back-colonization (boomerang) events from Macaronesia to Africa

Recent work in island biogeography has shown that back-colonization (‘boomerang’ events) from islands to continents have occurred more frequently than previously understoodWe report possibly the earliest inference of this pattern, by John Ball and Joseph Dalton Hooker in a book published in 1878

Downstream Self-Destruction of Storm Tracks

The Northern Hemisphere storm tracks have maximum intensity over the Pacific and Atlantic basins; their intensity is reduced over the continents downstream. Here, simulations with an idealized aquaplanet general circulation model are used to demonstrate that even without continents, storm tracks have a self-determined longitudinal length scale. Their length is controlled primarily by the planetary rotation rate and is similar to that of Earth’s storm tracks for Earth’s rotation rate. Downstream, storm tracks self-destruct: the downstream eddy kinetic energy is lower than it would be without the zonal asymmetries that cause localized storm tracks. Likely involved in the downstream self-destruction of storm tracks are the energy fluxes associated with them. The zonal asymmetries that cause localized storm tracks enhance the energy transport through the generation of stationary eddies, and this leads to a reduced baroclinicity that persists far downstream of the eddy kinetic energy maxima