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Sunshine hours (SSH) is an important meteorological parameter, loosely linked to temperature and precipitation, and highly relevant for various sectors such as agriculture or solar energy. Previous studies have already identified a correlation of European SSH with the thermal state of the North Atlantic. This paper investigates this relationship further by studying annual and monthly SSH of seven long-term Central European SSH series and comparing them to the Atlantic Multidecadal Oscillation (AMO) using Fourier Transformation, Monte Carlo simulation and non-linear optimization. The Fourier spectra of our annual SSH series have their strongest and highly significant peaks in the known AMO period of ~ 50 to ~ 80 years, supporting the hypothesis that European SSH and the AMO are linked. The optimized sinusoids of the seven SSH and the AMO series with these periods show substantial correlations with the corresponding data ( r  = 0.42–0.55 for SSH and 0.71 for the AMO). Extrapolating the sinusoids, we project a gradual decline in SSH across Central Europe by 9–16% from its current maximum over the next three decades, particularly pronounced in northern regions.

Precipitation in Europe shows natural fluctuations that differ considerably between seasons and geographical regions. A number of studies have linked local or seasonal rainfall variability to various long-distance air pressure differences in north–south or west–east direction. This paper presents the first continent-wide analysis of European rainfall variability on a month-by-month and country-by-country basis. We calculated Pearson r values for unsmoothed monthly rainfall data of 39 European countries over the period 1950–2019 with five potential climatic drivers, namely the North Atlantic Oscillation (NAO), the Arctic Oscillation (AO), the North Sea Caspian Pattern (NCP), and two indices of Mediterranean Oscillation (MOI2, WeMOI). For a variety of countries and months we found substantial and statistically significant r values of up to r = 0.7 and more. The dynamic temporal-spatial evolution of the Pearson correlations was mapped out across the continent, tracking the gradual or abrupt expansion, displacement and subsequent waning of the various effects over the course of the year. The correlation analysis was complemented by best subset multiple regression, controlling for intercorrelation of the potential drivers. Our results may help to improve short- to midterm rainfall prognoses in Europe and provide important calibration data for the further refinement of climate models.

Global mean annual temperature has increased by more than 1 °C during the past 150 years, as documented by thermometer measurements. Such observational data are, unfortunately, not available for the pre-industrial period of the Common Era (CE), for which the climate development is reconstructed using various types of palaeoclimatological proxies. In this analysis, we compared seven prominent hemispheric and global temperature reconstructions for the past 2000 years (T2k) which differed from each other in some segments by more than 0.5 °C. Whilst some T2k show negligible pre-industrial climate variability (“hockey sticks”), others suggest significant temperature fluctuations. We discuss possible sources of error and highlight three criteria that need to be considered to increase the quality and stability of future T2k reconstructions. Temperature proxy series are to be thoroughly validated with regards to (1) reproducibility, (2) seasonal stability, and (3) areal representativeness. The T2k represents key calibration data for climate models. The models need to first reproduce the reconstructed pre-industrial climate history before being validated and cleared for climate projections of the future. Precise attribution of modern warming to anthropogenic and natural causes will not be possible until T2k composites stabilize and are truly representative for a well-defined region and season. The discrepancies between the different T2k reconstructions directly translate into a major challenge with regards to the political interpretation of the climate change risk profile. As a rule of thumb, the larger/smaller the pre-industrial temperature changes, the higher/lower the natural contribution to the current warm period (CWP) will likely be, thus, reducing/increasing the CO2 climate sensitivity and the expected warming until 2100.

Temperatures in Oceania have risen by 0.5-1°C over the past 100 years, resulting e.g. in significant retreat of New Zealand’s glaciers. In order to better understand natural and anthropogenic contributions to this warming process, the observed climatic change has to be placed in a longer-term palaeotemperature context. Of particular interest is the Medieval Climate Anomaly (MCA, 1000-1200 AD), a recognized period of natural pre-industrial climate change, associated with marked temperature and hydroclimatic variability that is best known from the Northern Hemisphere. Temperature reconstructions for Oceania were traditionally based on two classical tree ring series. Here, we are enlarging the Oceania reference dataset with another 13 published temperature reconstructions from SE Australia, New Zealand and West Papua. These are based on a variety of proxy types, and help to geographically and methodologically augment the regional palaeoclimate database. The proxy series have been thoroughly compared and the MCA trends palaeoclimatologically mapped. Ten out of the 15 sites show a relatively warm MCA, compared to the last 1500 years, with warming generally occurring in the envelope period 900-1500 AD. In some sites of SE Australia and at the west coast of New Zealand’s South Island, warming appears to be delayed by 200-300 years. The end of the medieval warming at around 1500 AD occurred about two centuries later than on most other continents, suggesting a possible interhemispheric climate lag mechanism possibly involving deepwater circulation. Likely drivers for the medieval warming in Oceania are atmospheric-ocean cycles such as the Southern Annular Mode (SAM) and El Niño-Southern Oscillation (ENSO), in combination with solar activity changes. MCA palaeotemperature data are still lacking for large parts of Oceania, namely the arid and tropical parts of Australia, Micronesia, central and northern Polynesia, as well as central and eastern Melanesia, highlighting the need for future research.

Temperatures in Oceania have risen by 0.5-1°C over the past 100 years, resulting e.g. in significant retreat of New Zealand’s glaciers. In order to better understand natural and anthropogenic contributions to this warming process, the observed climatic change has to be placed in a longer-term palaeotemperature context. Of particular interest is the Medieval Climate Anomaly (MCA, 1000-1200 AD), a recognized period of natural pre-industrial climate change, associated with marked temperature and hydroclimatic variability that is best known from the Northern Hemisphere. Temperature reconstructions for Oceania were traditionally based on two classical tree ring series. Here, we are enlarging the Oceania reference dataset with another 13 published temperature reconstructions from SE Australia, New Zealand and West Papua. These are based on a variety of proxy types, and help to geographically and methodologically augment the regional palaeoclimate database. The proxy series have been thoroughly compared and the MCA trends palaeoclimatologically mapped. Ten out of the 15 sites show a relatively warm MCA, compared to the last 1500 years, with warming generally occurring in the envelope period 900-1500 AD. In some sites of SE Australia and at the west coast of New Zealand’s South Island, warming appears to be delayed by 200-300 years. The end of the medieval warming at around 1500 AD occurred about two centuries later than on most other continents, suggesting a possible interhemispheric climate lag mechanism possibly involving deepwater circulation. Likely drivers for the medieval warming in Oceania are atmospheric-ocean cycles such as the Southern Annular Mode (SAM) and El Niño-Southern Oscillation (ENSO), in combination with solar activity changes. MCA palaeotemperature data are still lacking for large parts of Oceania, namely the arid and tropical parts of Australia, Micronesia, central and northern Polynesia, as well as central and eastern Melanesia, highlighting the need for future research.

To evaluate the role of Total Solar Irradiance (TSI) on Northern Hemisphere (NH) surface air temperature trends it is important to have reliable estimates of both quantities. 16 different TSI estimates were compiled from the literature. 1/2 of these estimates are low variability and 1/2 are high variability. 5 largely-independent methods for estimating NH temperature trends were evaluated using: 1) only rural weather stations; 2) all available stations whether urban or rural (the standard approach); 3) only sea surface temperatures; 4) tree-ring temperature proxies; 5) glacier length temperature proxies. The standard estimates using urban as well as rural stations were anomalous as they implied a much greater warming in recent decades than the other estimates. This suggests urbanization bias might still be a problem in current global temperature datasets despite the conclusions of some earlier studies. Still, all 5 estimates confirm it is currently warmer than the late 19th century, i.e., there has been some global warming since 1850. For the 5 estimates of NH temperatures, the contribution from direct solar forcing for all 16 estimates of TSI was evaluated using simple linear least-squares fitting. The role of human activity in recent warming was then calculated by fitting the residuals to the UN IPCC's recommended anthropogenic forcings time series. For all 5 NH temperature series, different TSI estimates implied everything from recent global warming being mostly human-caused to it being mostly natural. It seems previous studies (including the most recent IPCC reports) that had prematurely concluded the former failed to adequately consider all the relevant estimates of TSI and/or to satisfactorily address the uncertainties still associated with NH temperature trend estimates. Several recommendations are provided on how future research could more satisfactorily resolve these issues.

The Areif El Naqa domal anticline in northeastern Sinai is part of the 'Syrian Arc' which represents an intraplate orogen that has been formed since the late Cretaceous by inversion of an older half-gaben system as a consequence of the collision of the African and Eurasian plates. The here studied pre- and syn-deformational Upper Albian to Lower Eocene sedimentary succession in the anticline was formed under shallow marine to hemipelagic conditions resulting in predominantly carbonate lithologies with only subordinate siliciclastic intercalations. The depositional history at Areif El Naqa has been reconstructed in terms of sequence stratigraphy on the basis of detailed sedimentological, biostratigraphical, and paleoecological investigations of ten sections including comparisons with age-equivalent successions further north and south as well as published data. Following a late Triassic-early Cretaceous extensional period, tectonically rather quiet conditions prevailed during deposition of the Albian-Turonian successions. Inversion started around the Coniacian. Three main phases of uplift have been determined for the Areif El Naqa anticline on the basis of evidence from lateral facies and thickness changes, local development of pronounced hiatuses, and in comparison to the sequence stratigraphic development in the tectonically quiet region of central east Sinai. The first major compressional phase is interpreted to have taken place in Coniacian-early Santonian times. It is characterized by pronounced facies and thickness changes which were documented in an earlier study byBartov et al. (1980). Nevertheless, inter-regional sea level changes still controlled deposition at Areif El Naqa during this period. The second pulse of tectonic uplift is indicated for the late Campanian-early Maastrichtian. This is based on siliciclastic deposits which are interpreted as having been reworked from older siliciclastic rocks uplifted in the anticlinal core. The third compressional pulse is inferred to be of middle Paleocene to early Eocene age as evidenced by a major hiatus in sections on the northern anticlinal flank. The uplift history at Areif El Naqa has been compared with the tectonic development in other parts of the Syrian Arc and in general seems to reflect major movements which occurred throughout the anticlines of the fold belt.[PUBLICATION ABSTRACT]

Does the excitation of ultrafast magnetization require direct interaction between the photons of the optical pump pulse and the magnetic layer? Here, we demonstrate unambiguously that this is not the case. For this we have studied the magnetization dynamics of a ferromagnetic cobalt/palladium multilayer capped by an IR-opaque aluminum layer. Upon excitation with an intense femtosecond-short IR laser pulse, the film exhibits the classical ultrafast demagnetization phenomenon although only a negligible number of IR photons penetrate the aluminum layer. In comparison with an uncapped cobalt/palladium reference film, the initial demagnetization of the capped film occurs with a delayed onset and at a slower rate. Both observations are qualitatively in line with energy transport from the aluminum layer into the underlying magnetic film by the excited, hot electrons of the aluminum film. Our data thus confirm recent theoretical predictions.

The continuing controversy about surgery for non-colorectal non-neuroendocrine liver metastases (NCRNNE) necessitates identifying risk factors of worsened outcomes to improve patient selection and survival. Prospectively collected data of 167 patients undergoing hepatectomy for NCRNNE were analyzed, and a comparison to a matched population of colorectal liver metastases (CLM) was performed. Overall survival (OS) (35 vs. 54 months; P  = 0.008) and recurrence-free survival (RFS) (15 vs. 29 months; P  = 0.004) of NCRNNE patients were significantly shorter compared to those with CLM. The best survival was found in the genitourinary (GU; OS, 45 months; RFS, 21 months) NCRNNE subgroup, whereas survival for gastrointestinal (GI) metastases was low (OS, 8 months; RFS, 7 months). Patients with renal cell carcinoma (RCC) showed excellent outcomes when compared to CLM (OS, 50 vs. 51 months; P  = 0.901). Extrahepatic disease (EHD) was identified as independent prognostic factor for reducing both RFS ( P  = 0.040) and OS ( P  = 0.046). The number of liver lesions ( P  = 0.024), residual tumor ( P  = 0.025), and major complications ( P  = 0.048) independently diminished OS. The degree of survival advantage by surgery is determined by the primary tumor site, EHD, the number of metastases, and residual tumor. Thus—even more than in CLM—these oncological selection criteria must prevail. GU metastases, especially RCC, represent a favorable subgroup.

Scientific Reports 6: Article number: 18970; published online: 06 January 2016; updated: 04 March 2016 The original version of this Article contained a typographical error in the spelling of the author Bharati Tudu, which was incorrectly given as Bahrati Tudu. This has now been corrected in the PDF and HTML versions of the Article.