Northern Hemisphere

During the last glacial-interglacial cycle, northern hemispheric (NH) ice-sheets experienced dramatic changes in radiative forcing, due to orbitally-driven insolation changes and varying greenhouse gas concentrations. This direct forcing caused temperature changes and eventually ablation anomalies. Orbital-scale variations in the atmospheric circulation caused anomalies in temperature advection and precipitation/snowfall that also strongly contributed to the mass balance and hence the time-evolution

The southern Levant has a long history of human habitation and it has been previously suggested that climatic changes during the Late Pleistocene-Holocene stimulated changes in human behaviour and society. In order to evaluate such linkages, it is necessary to have a detailed understanding of the climate record. We have conducted an extensive and up-to-date review of terrestrial and marine climatic conditions in the Levant and Eastern Mediterranean during the last 25,000 years. We firstly present data from general circulation models (GCMs) simulating the climate for the last glacial maximum (LGM), and evaluate the output of the model by reference to geological climate proxy data. We consider the types of climate data available from different environments and proxies and then present the spatial climatic ''picture'' for key climatic events. This exercise suggests that the major Northern Hemisphere climatic fluctuations of the last 25,000 years are recorded in the Eastern Mediterranean and Levantine region. However, this review also highlights problems and inadequacies with the existing data. r

, were measured by collecting 10 ice cores on the Agassiz ice cap, Ellesmere Island, Canada. ¹he deposition rates were 0)020 mBq cm\ 2 for 137 Cs and 0)0016 mBq cm\ 2 for 239#240 Pu, originating from Nagasaki. Assuming the radionuclides, excluding the amount fissioned from the explosion and deposited as local fallout, are deposited evenly throughout the Northern Hemisphere, 67% of the expected amount of 137 Cs reached the Arctic while 1)1% of 239#240 Pu reached the Arctic. ¹he results suggest that different transport mechanisms exist for various contaminants in the global transport system.

A perpetual January simulation of the global atmosphere has been used to study the climatology of the northern hemisphere winter, with particular reference to its synoptic characteristics and to changes induced by reductions in the concentration of Arctic sea ice. Lows were tracked using an objective scheme and were analyzed for a number measures of cyclone behavior. The qualitative features of the cyclone density and flux distributions compare well with observations, except in certain respects noted. Cyclone velocities and intensities are also presented and discussed. Decreases in sea ice concentration produced a monotonic but nonlinear warming in the lower troposphere and weakening and southward contraction of the midlatitude westerlies. Mean sea level pressure reductions were biased toward the western Arctic. There was a significant decrease in the speeds and intensities of cyclonic systems north of 45øN but little overall change in areal densities or in the arrangement of the major storm tracks. Some density maxima were displaced toward regions of opened up sea ice or in response to circulation changes. A number of aspects of the response are interpreted as being due to changes in thermal steering and baroclinicity or to nonlinear effects. Surprisingly, no significant expansion of cyclonic activity occurred in the central Arctic. The relative constancy of cyclone numbers and storm tracks is a response very different from that found in a similar study of the southern hemisphere.

A sulfuric acid aerosol model has been implemented in the global general circulation model ECHAM4. This model treats the formation, the development, and the transport of stratospheric sulfuric acid aerosol. The aerosol size distribution and the sulfuric acid mass fraction are calculated as a function of the H•SO4/H•O concentration, temperature, and air pressure in a size range between 0.001 and 2.58 •m. Binary homogeneous nucleation of H•SO4/H20, condensation and evaporation of H2SO4 and H20, Brownian coagulation and gravitational sedimentation are included. The microphysical model for stratospheric sulfate aerosol and a stratospheric sulfur chemistry are combined with a representation of the tropospheric sulfur chemistry. This tropospheric scheme accounts for the natural and anthropogenic emissions, chemistry, and dry and wet deposition of DMS, SO2, and SO•-. Globally and seasonally different SO2-and SO•-sources for stratospheric aerosol can therefore be taken into account. Results of a multiannual simulation show that the simulated SO2 and H2SO4 concentrations are generally in good agreement with available observations. The formation of new particles through homogeneous nucleation takes place in the tropical lower stratosphere and upper troposphere and in polar spring. The aerosol surface area density and the aerosol mass concentration reproduce lower stratospheric background conditions quite well. Effective radius and aerosol mixing ratio agree also with satellite and in situ measurements at Northern Hemisphere midlatitudes. 1. Introduction Stratospheric aerosol has various effects on the global climate system. It changes the chemical composition of the stratosphere because of heterogeneous reactions [Holmann and Solomon, 1989], provides condensation nuclei for the formation of polar stratospheric clouds and cirrus, and disturbs the radiative balance of the atmosphere in changing the albedo [Lacis et al., 1992]. These different atmospheric mechanisms are especially strong when the aerosol background layer is perturbed in response to strong volcanic eruptions or possibly in the future to high-speed civil transport aircraft. After the eruption of Mount Pinatubo (15.1øN, 120.4øE) in June 1991 a temperature increase in the lower stratosphere of •-2-3 K [Labitzke and McCormick, 1992] and a cooling of the global lower troposphere and the Earth's surface of • 0.5 K were detected [Dutton and Christy, 1992]. Furthermore, in 1992 and 1993 unusually strong ozone depletion due to chemical and dynamical processes was observed [Grant et al., 1994; Her-; Randel et al., 1995]. Stratospheric aerosol consists mainly of supercooled hydrated H2SO4 particles with a sulfuric acid mass fraction in the range of 50-80%. The particles form a persistent aerosol layer (Junge layer), which extends from the tropopause up to 30 km altitude. Height and maximum of the layer are seasonally and latitudinally dependent [Yue and Deepak, 1984]. The stratospheric aerosol particles are either directly formed in the stratosphere because of homogeneous nucleation or transported through the tropopause. In order to better understand the role of stratospheric aerosol in the atmospheric system several aerosol models were developed. At the end of the seventies, [ Turco et al., [1979] and [Turco et al., [1979] developed a one-dimensional (l-D) model, which was later refined by Toon et al. [1988] and Zhao et al. [1995]. Recently, Kgircher [1998] developed a coupled microphysical-chemical-dynamical box trajectory model for aircraft-generated liquid aerosols, which could also be applied to liquid H2SO4/HNOs/H•O aerosols. In the last years several studies with two-dimensional (2-D) chemistry transport models including sulfate aerosol microphysics were published in the literature. Theses studies focus on the impact of either aircraft emis-

Primary Eurostat data of EU imports of agricultural products from selected southern hemisphere countries-namely, South Africa, Argentina, Chile, Australia and New Zealand-was used to compare the exports from those countries to the EU for the period 1988 to 2000. The study starts with a general overview of the total and agricultural export performance of these selected countries in a global context and their specialization indexes for food. This is followed by a comparison of the total value, total mass and value per tonne of agricultural exports to the EU and of their exploitation of seasonal differences with the northern hemisphere in terms of relative emphasis on particular product groups and value/mass ratios of their major products. Comparison is made of the impact of their location relative to EU ports in terms of transport cost and duration of trips and the efficiency of their own ports. The conclusions reached is that in order to remain competitive, South Africa will have to add value to carefully selected non-seasonal products. Seasonal production will have to expand with a sharper focus on market windows becoming narrower due to research and development conducted by both northern and southern hemisphere competitors. The overview motivates an even more aggressive research and development (R&D) programme by South African agriculture and food industries in order to remain competitive on export markets, especially given the rapidly changing environment. For example, the introduction of much faster ships which will decrease South Africa's present advantage of having the shortest distance to the EU among the other southern hemisphere competitors.

Natural toxins, such as mycotoxins, have emerged as a significant factor affecting the safety image of cereal grains as a raw material for the food and feed industry. The aim of the present study was to investigate the contents of trichothecenes in representative samples of oats during official variety, nitrogen fertilization and organic farming trials in Finland, 1997–1999. Further objectives were to promote industry and commerce by selection of high-quality oat varieties for various applications. The official variety trials conducted at 8–10 locations were managed following standard protocol. There were 2 types of agronomy trial, the first included comparison of oat cultivars grown in conventional and organic farming systems at 6 locations, and the second used 5 nitrogen rates (0, 40, 80, 120 and 160 kg N ha-1) at 2 locations. Regardless of wet cold summer occurring in Finland during 1998, the concentrations of Fusarium toxins were lowest during this 3 year monitoring period. More...

Euphrasia includes perennial or annual green parasitic plants, and has a disjunct bipolar distribution except for one transtropical connection across the high mountains of Oceania. The disjunction is coupled with strikingly contrasting patterns of morphological diversity between the southern and northern hemispheres, making it an exciting model to study processes of evolutionary diversification which shaped present floras. We inferred the relationships among 51 species representing 14 of the 15 sections of the genus based on nrDNA ITS and cpDNA trnL intron, trnL-trnF and atpB-rbcL intergenic spacers. Maximum parsimony and Bayesian inference support monophyly of the genus and of several intrageneric groups characterized by morphology, ploidy level, and geographic range. Molecular phylogenetic dating using Bayesian ''relaxed" clock methods suggests that the earliest Euphrasia radiations occurred minimum 11-8 Mya with bipolarity being achieved 7-5 Mya. Biogeographic analyses using explicit modelbased approach inferred Eurasia as an ancestral area for the genus. The most parsimonious reconstruction found by a dispersal-vicariance analysis requires 17 dispersals to account for the current biogeographic pattern and supports Eurasian origin for Euphrasia. Both long-distance dispersal and across land vicariance can be invoked to explain the diversification in the genus, which experienced rapid radiations driven by new ecological opportunities of the late Pliocene and Pleistocene but also retained a set of local endemic or relict species of an earlier origin.

This paper examines the struggle economists in interwar Australia faced in coming to terms with new ideas on economic philosophy and whether they, in fact, registered upon Commonwealth economic policy. After being unusually great in 1931, with the Premiers' Plan, the significance of economists waned as political complacency, brought about by the recovery itself, took over. Economists reasserted their influence,

The east-west trending, post-orogenic subvertical Cleaver Dykes from the Great Bear Magmatic Arc are dated by the U-Pb (baddeleyite) method to be 1740 +5/−4 Ma. They have a mean direction of magnetization of D, I = 136.5 and 57.4 • , k = 64, α 95 = 4.5 • , based on samples from 17 diabase dykes, a mean location 65.7 • N, 118.03 • W, and a corresponding paleopole at 19.4 • N, 83.3 • W, A 95 = 6.1 • . Studies of baked contacts, country rocks distant from dykes, and later intrusions that cut them, show that the dykes became magnetized soon after intrusion. The paleopole is not significantly different from that obtained from the 1759 ± 1 Ma post-orogenic Jan Lake Granite from the Hudsonian Orogen in southeast Saskatchewan. These paleopoles fall among a cluster previously determined from post-orogenic overprints in a wide variety of rocks and geological settings across Laurentia. Their mean is 20.8 • N, 94.5 • W, A 95 = 5.2 • . Collectively they record a widespread remagnetization episode following the Hudsonian Orogeny, during which the polarity of the field remained constant. This single polarity interval (the Cleaver Superchron) has a mean age of approximately 1747 Ma, and its duration is at least 13 million years but is probably much longer. With further refinement, it could become a global statigraphical marker.

The impact of anthropogenic emissions on the global distributions and budgets of the main atmospheric sulphur species [namely dimethylsulphide (DMS), sulphur dioxide (SOz), and non-sea-salt (nss-) sulphate3 (SO]-)] is investigated using the IMAGES three-dimensional tropospheric chemistrytransport model. A previous study showed a broad consistency between modelled and observed concentrations of sulphur species for the present-day (c. 1985) atmosphere. Here, in order to assess the relative contributions of biogenic and man-made sources, we compare distributions calculated for the preindustrial atmosphere with the present-day results. The calculations show a large increase in the concentrations of sulphur dioxide and nss-sulphates since preindustrial times, amounting to a factor of 2-3 on global average, and reaching more than two orders of magnitude at the surface in some parts of the Northern Hemisphere. Biogenic species such as DMS are also shown to be influenced by industrialization through changes in the oxidizing capacity of the atmosphere. Over the most polluted areas, the increase in sulphates deposition is found to have reached a factor of 30.

The distribution of seismic units in deposits of the basins near the Antarctic-Scotia plate boundary is described based on the analysis of multichannel seismic reflection profiles. Five main seismic units are identified. The units are bounded by high-amplitude continuous reflectors, named a to d from top to bottom. The two older units are of different age and seismic facies in each basin and were generally deposited during active rifting and seafloor spreading.

Technical reports on operations and features of the Pierre Auger Observatory, including ongoing and planned enhancements and the status of the future northern hemisphere portion of the Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009.

Dinoflagellate cysts and XRF core scanning data from two marine sediment cores from embayments north (Bonavista Bay) and south (Placentia Bay) of Newfoundland show significant changes in ocean and atmospheric conditions of the SW Labrador Sea region during the last 5700 years. Fresh and cold conditions, probably accompanied by seasonal sea ice, prevailed both north and south of Newfoundland from c. 5.7 to 4.0 cal. kyr BP. This may be linked to intensified Labrador Current export of cold meltwater and/or sea ice from the Arctic, presumably related to warmer conditions in the northernmost latitudes and the prevalence of strong (north)westerly winds. After c. 4.0 cal. kyr BP, sea-surface conditions warmed up and sea ice decreased northeast of Newfoundland, but conditions were still cold south of Newfoundland. This suggests a decrease in Arctic meltwater export and westerly wind strength. After 2.9—2.5 cal. kyr BP, only minor changes in sea-surface conditions affected the study sites. S...

This NSF-funded, Phase 1 CCLI project effectively integrates scientific ocean drilling data and research (DSDP-ODP-IODP-ANDRILL) with education. We have developed, and are currently testing, a suite of data-rich inquiry-based classroom learning materials based on sediment core archives. These materials are suitable for use in introductory geoscience courses that serve general education students, early geoscience majors, and pre-service teachers. 'Science made

We examined spatial patterns of trends in ice phenology and duration for 65 waterbodies across the Great Lakes region (Minnesota, Wisconsin, Michigan, Ontario, and New York) during a recent period of rapid climate warming (1975-2004). Average rates of change in freeze (3.3 d decade 21) and breakup (22.1 d decade 21) dates were 5.8 and 3.3 times more rapid, respectively, than historical rates (1846-1995) for Northern Hemisphere waterbodies. Average ice duration decreased by 5.3 d decade 21. Over the same time period, average fall through spring temperatures in this region increased by 0.7uC decade 21 , while the average number of days with snow decreased by 5.0 d decade 21 , and the average snow depth on those days decreased by 1.7 cm decade 21. Breakup date and ice duration trends varied over the study area, with faster changes occurring in the southwest. Trends for each site were compared to static waterbody characteristics and meteorological variables and their trends. The trend toward later freeze date was stronger in large, low-elevation waterbodies; however, freeze date trends had no geographic patterns or relationships to meteorological variables. Variability in the strength of trends toward earlier breakup was partially explained by spatial differences in the rate of change in the number of days with snow cover, mean snow depth, air temperature (warmer locations showed stronger trends), and rate of change in air temperature. Differences in ice duration trends were explained best by a combination of elevation and the local rate of change in either temperature or the number of days with snow cover.

Chl-Zr 26 and Chl-ZML relationships. This important role of ocean physics indicates that the observed Chl changes primarily reflect biomass changes due to dampened or increased nutrient fluxes to the upper lit layers. Changes in the photoacclimation state of phytoplankton probably also intervene, without obscuring the global picture, however. Quantifying the respective role of both phenomena would require the parallel examination of Chl and other quantities more directly tied to biomass.

Snow cover is a highly variable land surface condition that exerts a strong control on the heat and moisture budget of the overlying atmosphere. Modeling studies based on long integrations of global circulation models (GCM) are normally carried out at very low resolution (typically coarser than 100 km) due to their high computational demand. On local scales, snow cover plays an important socioeconomic role, ranging from water management applications to outdoor recreation. These latter applications vary in horizontal resolution from a few hundred meters to a few kilometers, where small scale topography, land cover and local circulation effects play a significant role. In this study our focus will be on horizontal scales ranging from typical GCM global climate modeling to high resolution global weather forecasts. In the land surface component of a GCM (land surface model - LSM), snow cover temporal and spatial variability is mainly determined by the overlying atmospheric conditions. However, once snowfall settles on the ground, the sub-grid scale variability associated with complex terrain and land cover variability (not resolved at the model resolution) is parameterized following simple physical and/or empirical relations. The present study intends to access the impact of horizontal resolution in the European Centre for Medium-Range Weather Forecasts (ECMWF) land surface model (HTESSEL). HTESSEL is forced by the ECMWF operational weather forecasts since March 2006 to December 2009 (runs in offline/stand-alone mode). The control run is carried out at the horizontal resolution of the forecasts at TL799 (gaussian reduced grid N400 -about 25 km). Two lower horizontal resolutions are then tested: TL255 (gaussian reduced grid - about 80 km, same as the ERA-Interim reanalysis), and TL95 (gaussian reduced grid N48 - about 200 km). The length of the simulations is rather small (only 46 months), however global meteorological forcing at 25 km can only be accessed through the ECMWF recent weather forecasts. Such high resolution associated with the state of the art modeling and assimilation frameworks guarantees that the atmospheric conditions seen by the LSM are as close as possible to reality. To assure that the two lower horizontal resolution simulations have a good quality forcing, an energy/mass conserving remapping was applied when upscaling the forcing fields. Special care was taken for the upscaling of temperature, specific humidity, surface pressure and downward longwave radiation considering the changes in mean orography between resolutions. Snow cover simulations are validated against two daily observational products: 1) IMS Daily Northern Hemisphere Snow and Ice Analysis at 4 km resolution (National Snow and Ice Data Center) and 2) SNOWCLIM snow depth daily European domain at 0.1° resolution (German Weather Service). The present work is focused over Europe, namely in four domains: Alps, Central and Eastern Europe and Scandinavia, where conditional spatial sampling is performed in order to distinguish between complex versus flat terrain and forest versus exposed (low vegetation and bare ground) areas. The results are model dependent, but allow deriving important relations between resolution, orography and vegetation variability impacts on snow cover simulations.

Port Phillip Bay (PPB) is a large (1,930 km2), temperate embayment in southern Victoria, Australia. Extensive bay-wide surveys of PPB have occurred since 1840. In 1995/1996 the Commonwealth Scientific and Industrial Research Organization (CSIRO) Centre for Research on Introduced Marine Pests (CRIMP) undertook an intensive evaluation of the region with the aims of developing a comprehensive species list of native and introduced biota and contrasting previous bay-wide assessments with a current field survey in order to detect new incursions and discern alterations to native communities. Two methods were used to meet these aims: a re-evaluation of regional museum collections and published research in PPB to identify and determine the timing of introductions; and field surveys for benthic (infauna, epifauna and encrusting) organisms between September 1995 to March 1996. One hundred and sixty introduced (99) and cryptogenic (61) species were identified representing over 13% of the recorded species of PPB. As expected, the majority of these are concentrated around the shipping ports of Geelong and Melbourne. Invasions within PPB appear to be increasing, possibly due to an increase in modern shipping traffic and an increase in aquaculture (historically associated with incidental introductions); however the records of extensive biological surveys suggest that this may, in part, be an artefact of sampling effort. In contrast to Northern Hemisphere studies, PPB (and Southern Hemisphere introductions in general) have significantly different suites of successfully invading taxa. PPB is presented as one of the most invaded marine ecosystems in the Southern Hemisphere.

1] Marine sediments recorded a series of Heinrich events during the last glacial period, massive ice surges that deposited prominent layers of ice-rafted debris in the North Atlantic. Here we explore oceanic mechanisms that can potentially trigger and amplify the observed ice calving events. Simulations of abrupt glacial climate change with a coupled ocean-atmosphere-sea ice model show a substantial regional sea level rise in the North Atlantic in response to a collapse of the Atlantic meridional overturning circulation (MOC). The increased heat uptake of the global ocean after the MOC collapse leads to an additional rise in global sea level. We hypothesize that these sea level changes have the potential to destabilize Northern Hemisphere ice shelves and ice sheets and to trigger ice surges. Sea level rise due to ice calving and subsurface ocean warming provides two positive feedback mechanisms contributing to further destabilization of ice shelves and ice sheets.

The effect of Drake Passage on the Earth's climate is examined using an idealised coupled model. It is found that the opening of Drake Passage cools the high latitudes of the southern hemisphere by about 3°C and warms the high latitudes of the northern hemisphere by nearly the same amount. This study also attempts to determine whether the width and depth of the Drake Passage channel is likely to be an important factor in the thermal response. A deeper channel is shown to produce more southern cooling but the magnitude of the effect is not large. Channel geometry is relatively unimportant in the model because of a haline response that develops when the channel is first opened up. Published in

The Indonesian wildfires of 1997 released large amounts of trace gases and aerosols (e.g., $130 Tg of carbon monoxide (CO)) from September to November. Using the GEOS-CHEM model of tropospheric chemistry and transport, we conducted a study of this burning event, including sensitivity simulations, to estimate the impacts of the trace gas and aerosol emissions on tropospheric chemistry. The emissions from the fires were estimated using the Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) data product and fire-count data from the Along Track Scanning Radiometer (ATSR) World Fire Atlas as surrogates for biomass burning. The model captures most of the daily variations of CO and ozone (O 3) observed in the region affected by the pollution. Export of the pollution from the Indonesian region was primarily in the prevailing easterlies in the free troposphere to the tropical Indian Ocean where the bulk of the pollution lay between 20°N to 20°S from September to November. The model's tropospheric CO and O 3 columns were elevated by more than 50% and 10%, respectively, over the tropical Indian Ocean in a simulation with emissions from the fires relative to a simulation without the emissions. Another important export pathway was to the tropical and subtropical South Pacific Ocean in the southern subtropical jet. A more episodic pathway occurred to the tropics and subtropics of the North Pacific Ocean. By December, the tropospheric CO column from the fires had mixed zonally and somewhat symmetrically about the equator impacting both the Northern and Southern Hemisphere similarly. The model's CO column was elevated by 10-20% from 30°N to 45°S in December, by 5-10% poleward of 45°S, and by less than 5% poleward of 45°N. The relative impact of the fires was lower in the Northern Hemisphere, as the background CO column is typically higher there. The fires decreased the concentration of the hydroxyl radical (OH) in the model by more than 20% over much of the tropical Indian Ocean through consumption by CO, heterogeneous loss of odd-oxygen radicals (HO x) on black (BC) and organic carbon (OC) aerosols, and reduction of UV light by the aerosols. The net direct, shortwave radiative forcing at the top of the atmosphere of OC and BC aerosols from the fires was relatively small, as their forcings were similar, but of opposite signs. The net forcing at the surface, however, was large, about À10 W m À2 over most of the tropical Indian Ocean and as low as À150 W m À2 over the burning regions in Indonesia, indicating that aerosols from the fires significantly perturbed the tropical radiative budget. The calculated forcing of O 3 was minor relative to those of BC and OC aerosols.

Ethnopharmacological relevance: In Russian traditional medicine, an extract from the mushroom Inonotus obliquus (Fr.) Pil´at is used as an anti-tumor medicine and diuretic. It has been reported that Inonotus obliquus has therapeutic effects, such as anti-inflammatory, immuno-modulatory and hepatoprotective effects. This study was designed to investigate the chemical composition and biological properties of aqueous and ethanolic extracts of Inonotus obliquus from Finland, Russia, and Thailand. Their antioxidative, antimicrobial, and antiquorum properties were tested as well as the cytotoxicity on various tumor cell lines.

This NSF-funded, Phase 1 CCLI project effectively integrates scientific ocean drilling data and research (DSDP-ODP-IODP-ANDRILL) with education. We have developed, and are currently testing, a suite of data-rich inquiry-based classroom learning materials based on sediment core archives. These materials are suitable for use in introductory geoscience courses that serve general education students, early geoscience majors, and pre-service teachers. 'Science made accessible' is the essence of this goal. Our team consists of research and education specialists from institutions ranging from R1 research to public liberal arts to community college. We address relevant and timely 'Big Ideas' with foundational geoscience concepts and climate change case studies, as well transferable skills valued in professional settings. The exercises are divided into separate but interrelated modules including: introduction to cores, seafloor sediments, microfossils and biostratigraphy, pale...

Abstract. Time series of ocean properties provide a measure of global ice volume and monitor key features of the wind-driven and Censity-driven circulations over the past 400,000 years. Cycles with periods near 23,000, 41,000, and 100,000 years dominate this climatic narrative. When the narrative is examined in a geographic array of time series, the phase of each climatic oscillation is seen to progress through the system in essentially the same geographic sequence in all three cycles. We argue that

Species in the genus Castanea are widely distributed in the deciduous forests of the Northern Hemisphere from Asia to Europe and North America. They show floristic similarity but differences in chestnut blight resistance especially among eastern Asian and eastern North American species. Phylogenetic analyses were conducted in this study using sequences of three chloroplast noncoding trnT-L-F regions. The trnT-L region was found to be the most variable and informative region. The highest proportion of parsimony informative sites, more and larger indels, and higher pairwise distances between taxa were obtained at trnT-L than at the other two regions. The high A+T values (74.5%) in the Castanea trnT-L region may explain the high proportion of transversions found in this region where as comparatively lower A+T values were found in the trnL intron (68.35%) and trnL-F spacer (70.07%) with relatively balanced numbers of transitions and transversions. The genus Castanea is supported as a monophyletic clade, while the section Eucastanon is paraphyletic. C. crenata is the most basal clade and sister to the remainder of the genus. The three Chinese species of Castanea are supported as a single monophyletic clade, whose sister group contains the North American and European species. There is consistent but weak support for a sister–group relationship between the North American species and European species.

A generalized coccolithophore bloom classifier has been developed for use with ocean color imagery. The bloom classifier was developed using extracted satellite reflectance data from SeaWiFS images screened by the default bloom detection mask. In the current application, we extend the optical water type (OWT) classification scheme by adding a new coccolithophore bloom class formed from these extracted reflectances. Based on an in situ coccolithophore data set from the North Atlantic, the detection levels with the new scheme were between 1,500 and 1,800 coccolithophore cells/mL and 43,000 and 78,000 liths/mL. The detected bloom area using the OWT method was an average of 1.75 times greater than the default bloom detector based on a collection of SeaWiFS 1 km imagery. The versatility of the scheme is shown with SeaWiFS, MODIS Aqua, CZCS and MERIS imagery at the 1 km scale. The OWT scheme was applied to the daily global SeaWiFS imagery mission data set (years 1997-2010). Based on our results, average annual coccolithophore bloom area was more than two times greater in the southern hemisphere compared to the northern hemisphere with values of 2.00 × 10 6 km 2 and 0.75 × 10 6 km 2 , respectively. The new algorithm detects larger bloom areas in the Southern Ocean compared to the default algorithm, and our revised global annual average of 2.75 × 10 6 km 2 is dominated by contributions from the Southern Ocean.

The responses of ground beetles to an urbanisation gradient (forest-suburban area-urban park) were studied in and near Sorø, South Zealand, Denmark, during April-October 2004. The average number of species per trap did not differ significantly among the three urbanisation stages. The average number of forest species was significantly higher in the forest area (6.2 species/trap) than in either the suburban (4.12 spp/trap) or the urban (3.7 spp/trap) areas. Both the number of open-habitat species (1.8 spp/trap), and the generalist species (2.3 spp/trap) were highest in the urban area. The number of predaceous species was highest in the forest area (8.1 spp/trap), while the number of omnivorous species was highest in the urban area (0.9 spp/trap). Multivariate statistical procedures (NMDS, Sorensen similarity index) also confirmed that species composition changed remarkably along the forest-suburban-urban gradient. The highest number of species (S ¼ 37) was found at the urban area, deviating from trends at other northern hemisphere sites (Canada, Finland) where the overall species richness was highest at the forest habitats. Urban green areas, including forest patches contribute to the quality of urban life and thus should be conserved. Apart from their recreational value, which is widely appreciated and enjoyed by human inhabitants, such green urban spaces provide seemingly adequate habitat for numerous species of ground beetles found in less developed forest areas some distance from the city core. (Z. Elek). a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / a c t o e c 1146-609X/$ -see front matter ª a c t a o e c o l o g i c a 3 2 ( 2 0 0 7 ) 1 0 4 -1 1 1

Environmental indicators must have a predictable relationship with stressors to be of value in ecological assessments. We evaluated the information provided by commonly implemented monitoring indicators as a means of assessing of the level of ecological impact experienced by coastal lagoons in New South Wales, Australia. Existing data for environmental variables in coastal lagoons were correlated with independent estimates of catchment disturbance. There were few relationships between the monitoring variables (particularly water chemistry) and nutrient loads and catchment land use. Data from NSW catchments and lagoons were compared to analogous data from published northern hemisphere studies and it was clear that stressor variables were up to one to two orders of magnitude smaller in NSW, potentially explaining the lack of relationships with recognised indicators.Our study has highlighted the importance of using a range of indicators to assess trends in ecological condition of an estuarine ecosystem, particularly where stressor levels are not great. Using water quality as the sole means of determining lagoon condition was simply inadequate in NSW lagoons. We recommended that ecological outcome indicators such as algal abundance (macro and micro) and turbidity were most likely to show interpretable patterns at low to moderate nitrogen loadings (<40 kg Ha−1 yr−1) and that these should form the basis of estuarine trend monitoring in NSW lagoons. The demonstrated value of seagrass and macroalgal monitoring in estuaries with moderate to high nutrient loadings suggests that these indicators should not be overlooked when planning monitoring programs, recognising, however, they will not have strong discrimination at lower catchment loadings.

We report results from the highest-resolution simulations of global warming yet performed with an atmospheric general circulation model. We compare the climatic response to increased greenhouse gases of the National Center for Atmospheric Research (NCAR) climate model, CCM3, at T42 and T170 resolutions (horizontal grid spacing of 300 and 75 km respectively). All simulations use prescribed sea surface temperatures (SST). Simulations of the climate of 2100 AD use SSTs based on those from NCAR coupled model, Climate System Model (CSM). We find that the global climate sensitivity and large-scale patterns of climate change are similar at T42 and T170. However, there are important regional scale differences that arise due to better representation of topography and other factors at high resolution. Caution should be exercised in interpreting specific features in our results both because we have performed climate simulations using a single atmospheric general circulation model and because we used with prescribed sea surface temperatures rather than interactive ocean and sea-ice models.

Analysis of an extensive new molecular dataset for the moss class Polytrichopsida provides convincing support for many traditionally recognised genera and identifies higher level phylogenetic structure with a strong geographic component. A large apical clade that is most diverse in the northern hemisphere is subtended by a grade of southern temperate and tropical genera, while the earliest diverging lineages have widely separated relictual distributions. However, there is strongly supported topological incongruence between the nuclear 18S rRNA gene tree and the chloroplast and mitochondrial data for the positions of some taxa and notably for the status of Pogonatum. While Pogonatum is unambiguously paraphyletic in the 18S tree, it is well supported as monophyletic by the combined chloroplast and mitochondrial data, this being corroborated by several distinctive morphological synapomorphies and a 51-53 bp deletion in the rps4-trnS spacer. We explore various reticulate historical processes and methodological issues as possible explanations for incongruence, and suggest that either (1) the 18S topology is an artefact created by convergence of substitutions at specific sites due to functional and/or molecularstructural constraints not accounted for by the model, or (2) the incongruence is a product of ancient hybridization events. Under the latter scenario, incongruent topologies for Pogonatum are parsimoniously explained if Polytrichum (including Polytrichastrum sect. Aporotheca) is ultimately descended from a hybridization event involving an extinct maternal taxon derived from the branch ancestral to the combined Pogonatum/Polytrichum s.l. clade, and a paternal taxon belonging to (or ancestral to) the apical Pogonatum group to which the majority of extant species belong. Numerous novel relationships of taxonomic and evolutionary significance are supported. Notably, both Polytrichastrum and Oligotrichum are polyphyletic. While Polytrichastrum sect. Aporotheca is closely related to Polytrichum, other species, including the type, are not. The large majority of Oligotrichum species sampled occur in one of two distantly related clades with predominantly northern and southern hemisphere distributions, respectively, implying convergent evolution of this morphology in each of the two temperate zones.

The oldest ice rafted material (IRD) on the V0ring Plateau is dated to about 11 Ma, and is regarded as evidence that glaciers extended to sea level somewhere around the Nordic Seas at this time. We estimate that the major glaciations of Scandinavia and the Barents Sea-Svalbard area started at 2.5-2.8 Ma, when the amount of IRD on the Voring Plateau increased strongly, the deep sea 8180 curves indicate the onset of Northern Hemisphere glaciations, and the climate in The Netherlands was so cold that a major glaciation of Scandinavia is inferred. Most of the time until 0.9 Ma, the ice sheets were of intermediate size; they probably reached the coastal zone of western Norway for long periods. The center of glaciation is inferred to have been further north than during the later glaciations, and we speculate that this was the period of maximum glacial erosion of the Barents Sea. The largest glaciations, and also the warmest interglacials occurred during the last 900 kyrs, when the 100 kyr astronomic cycle became important. For the last glaciation, the Weichselian, the glacial fluctuations are known in greater detail both for Scandinavia and the Svalbard-Barents Sea region. In Scandinavia the glacial fluctuations apparently followed the 23 kyr precession cycle, whereas in the Barents Sea they followed the 41 kyr tilt cycle. In both areas more than one advance reached beyond the coast. We use the Weichselian record to "calibrate" the interpretation of more indirect evidences of glacial fluctuations, and apply the latter to the Scandinavian and Barents Sea glacial history since 2.5 Ma.

The Gnaphalieae are a group of sunflowers that have their greatest diversity in South America, Southern Africa, and Australia. The objective of this study was to reconstruct a phylogeny of the South African Gnaphalieae using sequence data from two noncoding chloroplast DNA sequences, the trnL intron and trnL/trnF intergenic spacer. Included in this investi- gation are the genera of the

In the mid-latitudes of the North Atlantic Ocean, six large iceberg surges, called Heinrich events, have been recognised between 60 and 10 kyr BP. They are characterised by meltwater events associated with iceberg discharges from both the Laurentide and the Fennoscandian-Greenland ice sheets. The hydrological conditions associated with these surges show changes in sea surface temperature (2}63C drop) and in sea surface salinity (1}3 decrease). Carbon isotopic analyses tend to show that the thermohaline circulation is a!ected by such discharges with a signi"cant decrease in the ventilation of deep waters. During the same period, ice cores record large climatic #uctuations, called Dansgaard-Oeschger events, which have been recognised in the North Atlantic Ocean and in the Norwegian Sea, and more recently, in various sedimentary environments world wide.

The mollusc disappearance-extinction events throughout the Mediterranean Pliocene suggest the definition of four faunistic units [Mediterranean Pliocene Molluscan Units (MPMUs)]. The bivalve taxonomic diversity, the paleobiogeographic significance and the chronological classification of each unit are analyzed in detail. The boundaries of the MPMUs approximate the major climatic changes of the Northern Hemisphere, respectively at 3.0, 2.5 and 2.1 Ma. On the whole, the molluscan fauna changes (356 species of shallow water bivalves have been considered ) record the transition from a tropical unit (MPMU1) to a biogeographic unit (MPMU4) comparable with that of the Recent Mediterranean.