Geological structure and composition of the Curonian Spit (Baltic Sea)

The paper presents new data on geology of the Curonian Spit based on results of the study of data on the engineering-geological transect compiled during the construction of gas pipe in the Russian sector of the spit. The data show that, along with eolian sand, peat deposits recovered in both its Russian and Lithuanian sectors make up a significant portion of the spit (data on the Lithuanian sector are adopted from the available literature). Based on new data, existing concepts on geology, paleogeography, geoecology, and stability of the Curonian Spit are discussed and refined.     

Changes in transfer functions with time

The paper contains data on the transfer functions of the electromagnetic field of the Earth and their changes with time.The results show that these changes are caused by the instability of parameters of the external sources of the geomagnetic field variations in high latitudes and by the changes in the physical properties of rocks and deep matter in the region of recordings of electromagnetic field components.A statement is made that under certain conditions the observations of changes in transfer functions of the electromagnetic field of the Earth can be used as long-term forerunners of earthquakes.     

A verification framework for interannual-to-decadal predictions experiments

Decadal predictions have a high profile in the climate science community and beyond, yet very little is known about their skill. Nor is there any agreed protocol for estimating their skill. This paper proposes a sound and coordinated framework for verification of decadal hindcast experiments. The framework is illustrated for decadal hindcasts tailored to meet the requirements and specifications of CMIP5 (Coupled Model Intercomparison Project phase 5). The chosen metrics address key questions about the information content in initialized decadal hindcasts. These questions are: (1) Do the initial conditions in the hindcasts lead to more accurate predictions of the climate, compared to un-initialized climate change projections? and (2) Is the prediction model’s ensemble spread an appropriate representation of forecast uncertainty on average? The first question is addressed through deterministic metrics that compare the initialized and uninitialized hindcasts. The second question is addressed through a probabilistic metric applied to the initialized hindcasts and comparing different ways to ascribe forecast uncertainty. Verification is advocated at smoothed regional scales that can illuminate broad areas of predictability, as well as at the grid scale, since many users of the decadal prediction experiments who feed the climate data into applications or decision models will use the data at grid scale, or downscale it to even higher resolution. An overall statement on skill of CMIP5 decadal hindcasts is not the aim of this paper. The results presented are only illustrative of the framework, which would enable such studies. However, broad conclusions that are beginning to emerge from the CMIP5 results include (1) Most predictability at the interannual-to-decadal scale, relative to climatological averages, comes from external forcing, particularly for temperature; (2) though moderate, additional skill is added by the initial conditions over what is imparted by external forcing alone; however, the impact of initialization may result in overall worse predictions in some regions than provided by uninitialized climate change projections; (3) limited hindcast records and the dearth of climate-quality observational data impede our ability to quantify expected skill as well as model biases; and (4) as is common to seasonal-to-interannual model predictions, the spread of the ensemble members is not necessarily a good representation of forecast uncertainty. The authors recommend that this framework be adopted to serve as a starting point to compare prediction quality across prediction systems. The framework can provide a baseline against which future improvements can be quantified. The framework also provides guidance on the use of these model predictions, which differ in fundamental ways from the climate change projections that much of the community has become familiar with, including adjustment of mean and conditional biases, and consideration of how to best approach forecast uncertainty.     

Real-time multi-model decadal climate predictions

We present the first climate prediction of the coming decade made with multiple models, initialized with prior observations. This prediction accrues from an international activity to exchange decadal predictions in near real-time, in order to assess differences and similarities, provide a consensus view to prevent over-confidence in forecasts from any single model, and establish current collective capability. We stress that the forecast is experimental, since the skill of the multi-model system is as yet unknown. Nevertheless, the forecast systems used here are based on models that have undergone rigorous evaluation and individually have been evaluated for forecast skill. Moreover, it is important to publish forecasts to enable open evaluation, and to provide a focus on climate change in the coming decade. Initialized forecasts of the year 2011 agree well with observations, with a pattern correlation of 0.62 compared to 0.31 for uninitialized projections. In particular, the forecast correctly predicted La Niña in the Pacific, and warm conditions in the north Atlantic and USA. A similar pattern is predicted for 2012 but with a weaker La Niña. Indices of Atlantic multi-decadal variability and Pacific decadal variability show no signal beyond climatology after 2015, while temperature in the Niño3 region is predicted to warm slightly by about 0.5 °C over the coming decade. However, uncertainties are large for individual years and initialization has little impact beyond the first 4 years in most regions. Relative to uninitialized forecasts, initialized forecasts are significantly warmer in the north Atlantic sub-polar gyre and cooler in the north Pacific throughout the decade. They are also significantly cooler in the global average and over most land and ocean regions out to several years ahead. However, in the absence of volcanic eruptions, global temperature is predicted to continue to rise, with each year from 2013 onwards having a 50 % chance of exceeding the current observed record. Verification of these forecasts will provide an important opportunity to test the performance of models and our understanding and knowledge of the drivers of climate change.     

Changes in temperature and precipitation extremes in the CMIP5 ensemble

Twenty-year temperature and precipitation extremes and their projected future changes are evaluated in an ensemble of climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5), updating a similar study based on the CMIP3 ensemble. The projected changes are documented for three radiative forcing scenarios. The performance of the CMIP5 models in simulating 20-year temperature and precipitation extremes is comparable to that of the CMIP3 ensemble. The models simulate late 20th century warm extremes reasonably well, compared to estimates from reanalyses. The model discrepancies in simulating cold extremes are generally larger than those for warm extremes. Simulated late 20th century precipitation extremes are plausible in the extratropics but uncertainty in extreme precipitation in the tropics and subtropics remains very large, both in the models and the observationally-constrained datasets. Consistent with CMIP3 results, CMIP5 cold extremes generally warm faster than warm extremes, mainly in regions where snow and sea-ice retreat with global warming. There are tropical and subtropical regions where warming rates of warm extremes exceed those of cold extremes. Relative changes in the intensity of precipitation extremes generally exceed relative changes in annual mean precipitation. The corresponding waiting times for late 20th century extreme precipitation events are reduced almost everywhere, except for a few subtropical regions. The CMIP5 planetary sensitivity in extreme precipitation is about 6 %/°C, with generally lower values over extratropical land.     

Studying precipitation chemistry by multivariate analysis based on data of rural stations in Russian Barents Region

Multivariate analysis methods have been applied to studying variations in the concentrations of Ag, Al, As, B, Ba, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Si, Sn, Sr, Th, Tl, U, V, Zn, Cl^?, NO ₃ ^? , SO ₄ ^2? as components of precipitation at 11 rural stations under project “Ecogeochemistry of Barents Region”. Hierarchic factor analysis revealed the structure and space-time distribution of seven first-order factors and two second-order factors. The combinations of ingredients that determine the composition of first-order factors characterize the sources of precipitation composition, which have been found to be specific and volatile products of fuel oil and coal combustion, marine and earth aerosols, and biogenic processes. Second-order factors showed two independent sets of components, which are typical of the chemistry of precipitation at the examined stations in winter and summer. Step-by-step discriminant and cluster analysis made it possible to classify the observational stations by precipitation chemistry and demonstrate the extent of difference between them.     

The evolution of Cenozoic explosive volcanism: The Iceland Plume

This paper reviews original and published data on the abundance and composition of pyroclastics due to explosive discharges by volcanoes on the Iceland Plume. The pyroclastics were deposited in the Cenozoic sediments in the North Atlantic Ocean and in the Norwegian-Greenland basin. The DSDP and ODP initial reports (70 deep wells), 100 geologic columns sampled during cruises of the R/Vs Akademik Kurchatov and Mikhail Lomonosov furnished the database from which we constructed stratigraphic and areal-maps of pyroclastics abundance and computed the distribution of the volumes and amounts of pyroclastic layers over the stratigraphic intervals of the Cenozoic sedimentary sequence. The distribution of these layers was found to be cyclic; the highest frequency occurred during the Quaternary. Basaltoid pyroclastics prevailed in the late Paleocene and Early Eocene. The Oligocene has typically subalkaline ankaramite pyroclastics. From the Miocene until the Quaternary the pyroclastics became bimodal (basalt-rhyolite) and high potassium rhyolite pyroclastics appeared. This evolution seems to have been caused by crystallization differentiation of basaltoid magmas in magma chambers that came into being in prespreading grabens where a thick (> 20 km) sequence of volcanic rocks accumulated to produce a dipping reflector.     

Geological history and magmatism of the Jan Mayen microcontinent (Polar Atlantic)

Two main events determined the formation, geological history, magmatism, and geodynamics of the Jan Mayen microcontinent: (1) drift of this segment of the Laurasian plate over the Iceland plume in the Early Paleogene; (2) propagation of the rift zone of the mid-Atlantic Ridge into this region and separation of the Jan Mayen lithospheric block from northeastern Greenland. The lithosphere was reduced at the block boundary when it was separated. This process was accompanied by the formation of depressions intruded by magma of the Iceland plume, which resulted in the appearance of a new volcanic center with active volcanoes of the central type. They supplied pyroclastic material to the sedimentary cover of the expanding Norwegian?Greenland Basin in the Eocene and Oligocene. The wedging of the Jan Mayen plate (microcontinent) into the triple junction of the plates (Greenland, Eurasian, Jan Mayen) promoted intense volcanism and the formation of two large volcanic complexes: (1) the Greenland?Faroes and the (2) Trail?Vøring. Recent volcanoes of the Jan Mayen hot spot are fed by magma from the Iceland plume as well as from relict and newly formed cambers in a zone of deep-seated Jan Mayen transform faults.     

Structure of chemical elements deposited with atmospheric precipitation in the north of the European territory of Russia derived with multivariate analysis methods

Data on deposition density of Ag, Al, As, B, Ba, Bi, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Si, Sn, Sr, Th, Tl, U, V, Zn, Cl^?, NO ₃ ^? , and SO4 ₄ ^2? in atmospheric precipitation were derived at 11 observation stations in the northern part of the European territory of Russia (ETR). Three sets (factors) of chemical indices that are mutually independent and determine the precipitation chemical content over that territory were revealed by using the hierarchical factor analysis of deposited density of chemical ingredients studied. These are two first-order factors: one is presented with the elements of a “marine” origin; the second is associated with biogenic elements. The second-order factor is formed by the ingredients characteristic of the combustion products of different fossil fuels. The structure and space-time distribution of factors are considered. The discriminant and cluster analyses allowed to classify the observation stations considered by the atmospheric precipitation chemistry and to show that Amderma, Vorkuta, Arkhangelsk, and Kargopol stations mostly differ from each other.     

The relationship between sea surface temperature anomalies and atmospheric circulation in GCM experiments

Several 19-year integrations of the Hamburg version of the ECMWF/T21 general circulation model driven by the monthly mean sea surface temperature (SST) observed in 1970–1988 were examined to study extratropical response of the atmospheric circulation to SST anomalies in the Northern Hemisphere in winter. In the first 19-years run SST anomalies were prescribed globally (GAGO run), and in two others SST monthly variability was limited to extratropical regions (MOGA run) and to tropics (TOGA run), respectively. A canonical correlation analysis (CCA), which select from two time-dependent fields optimally correlated pairs of patterns, was applied to monthly anomalies of SST in the North Alantic and Pacific Oceans and monthly anomalies of sea level pressure and 500 hPa geopotential height in the Northern Hemisphere. In the GAGO run the best correlated atmospheric pattern is global and is characterized by north-south dipole structures of the same polarity in the North Atlantic and the North Pacific sectors. In the MOGA and TOGA experiments the atmospehric response is more local than in the GAGO run with main centers in the North Atlantic and North Pacific, respectively. The extratropical response in the GAGO run is not equal to the sum of the responses in the MOGA and TOGA runs. The artificial meridional SST gradients at 25°–30°N probably influence the results of the MOGA and TOGA runs. The atmopsheric modes found by the CCA were compared with the normal modes of the barotropic vorticity equation linearized about the 500 hPa. winter climate. The normal modes with smallest eigenvalues are similar to the model leading variability modes and canonical patterns of 500 hPa geopotential height. The corresponding eigenvectors of the adjoint operator, which represent an external forcing optimal for exciting normal modes, have a longitudinal structure with maxima in regions characterized by enhanced high frequency baroclinic activity over both oceans.