Statistics of the seasonal cycle of the 1951-2000 surface temperature records in Italy

We present an analysis of seasonal cycle of the last 50 years of records of surface temperature in Italy. We consider two data sets which synthesize the surface temperature fields of Northern and Southern Italy. Such data sets consist of records of daily maximum and minimum temperature. We compute the best estimate of the seasonal cycle of the variables considered by adopting the cyclograms' technique. We observe that in general the minimum temperature cycle lags behind the maximum temperature cycle, and that the cycles of the Southern Italy temperatures records lag behind the corresponding cycles referring to Northern Italy. All seasonal cycles lag considerably behind the solar cycle. The amplitude and phase of the seasonal cycles do not show any statistically significant trend in the time interval considered.Comment: 30 pages, 6 figures, submitted to IJ

Does the Danube exist? Versions of reality given by various regional climate models and climatological datasets

We present an intercomparison and verification analysis of several regional climate models (RCMs) nested into the same run of the same Atmospheric Global Circulation Model (AGCM) regarding their representation of the statistical properties of the hydrological balance of the Danube river basin for 1961-1990. We also consider the datasets produced by the driving AGCM, from the ECMWF and NCEP-NCAR reanalyses. The hydrological balance is computed by integrating the precipitation and evaporation fields over the area of interest. Large discrepancies exist among RCMs for the monthly climatology as well as for the mean and variability of the annual balances, and only few datasets are consistent with the observed discharge values of the Danube at its Delta, even if the driving AGCM provides itself an excellent estimate. Since the considered approach relies on the mass conservation principle and bypasses the details of the air-land interface modeling, we propose that the atmospheric components of RCMs still face difficulties in representing the water balance even on a relatively large scale. Their reliability on smaller river basins may be even more problematic. Moreover, since for some models the hydrological balance estimates obtained with the runoff fields do not agree with those obtained via precipitation and evaporation, some deficiencies of the land models are also apparent. NCEP-NCAR and ERA-40 reanalyses result to be largely inadequate for representing the hydrology of the Danube river basin, both for the reconstruction of the long-term averages and of the seasonal cycle, and cannot in any sense be used as verification. We suggest that these results should be carefully considered in the perspective of auditing climate models and assessing their ability to simulate future climate changes.Comment: 25 pages 8 figures, 5 table

Accessing extremes of mid-latitudinal wave activity: methodology and application

A statistical methodology is proposed and tested for the analysis of extreme values of atmospheric wave activity at mid-latitudes. The adopted methods are the classical block-maximum and peak over threshold, respectively based on the generalized extreme value (GEV) distribution and the generalized Pareto distribution (GPD). Time-series of the ‘Wave Activity Index’ (WAI) and the ‘Baroclinic Activity Index’ (BAI) are computed from simulations of the General Circulation Model ECHAM4.6, which is run under perpetual January conditions. Both the GEV and the GPD analyses indicate that the extremes ofWAI and BAI areWeibull distributed, this corresponds to distributions with an upper bound. However, a remarkably large variability is found in the tails of such distributions; distinct simulations carried out under the same experimental setup provide sensibly different estimates of the 200-yr WAI return level. The consequences of this phenomenon in applications of the methodology to climate change studies are discussed. The atmospheric configurations characteristic of the maxima and minima of WAI and BAI are also examined

Annual and semiannual cycles of midlatitude near-surface temperature and tropospheric baroclinicity: reanalysis data and AOGCM simulations

Abstract. Seasonal variability in near-surface air temperature and baroclinicity from the ECMWF ERA-Interim (ERAI) reanalysis and six coupled atmosphere–ocean general circulation models (AOGCMs) participating in the Coupled Model Intercomparison Project phase 3 and 5 (CMIP3 and CMIP5) are examined. In particular, the annual and semiannual cycles of hemispherically averaged fields are studied using spectral analysis. The aim is to assess the ability of coupled general circulation models to properly reproduce the observed amplitude and phase of these cycles, and investigate the relationship between near-surface temperature and baroclinicity (coherency and relative phase) in such frequency bands. The overall results of power spectra agree in displaying a statistically significant peak at the annual frequency in the zonally averaged fields of both hemispheres. The semiannual peak, instead, shows less power and in the NH seems to have a more regional character, as is observed in the North Pacific Ocean region. Results of bivariate analysis for such a region and Southern Hemisphere midlatitudes show some discrepancies between ERAI and model data, as well as among models, especially for the semiannual frequency. Specifically, (i) the coherency at the annual and semiannual frequency observed in the reanalysis data is well represented by models in both hemispheres, and (ii) at the annual frequency, estimates of the relative phase between near-surface temperature and baroclinicity are bounded between about ±15° around an average value of 220° (i.e., approximately 1-month phase shift), while at the semiannual frequency model phases show a wider dispersion in both hemispheres with larger errors in the estimates, denoting increased uncertainty and some disagreement among models. The most recent CMIP climate models (CMIP5) show several improvements when compared with CMIP3, but a degree of discrepancy still persists though masked by the large errors characterizing the semiannual frequency. These findings contribute to better characterizing the cyclic response of current global atmosphere–ocean models to the external (solar) forcing that is of interest for seasonal forecasts

On the mid-latitude tropopause height and the orographic-baroclinic adjustment theory

In the extratropics the analysis of the time–space structure of the dynamical tropopause shows a marked signature of nonpropagating, low-frequency (time-scale >10 d), ultra-long (zonal wavenumber <5) waves. This suggests the extension of theories relating the tropopause height to the baroclinic adjustment to the orographic-baroclinic disturbances, generally operating in the low-frequency domain. Such an extension is here proposed. By analysing Eady modes in a Boussinesq atmosphere, it has been found that the form-drag instability must be accounted for in an extended theory of baroclinic neutralization. The produced unstable standing waves carry a poleward large amount of heat at planetary scale for most of the external parameter settings and their spatial structure strongly resembles the observed winter mid-latitude eddy fields. Furthermore, we show how a simple representation of the stratosphere affects the tropopause neutralization requirements

“Crystalline Syndiotactic Polystyrene as Reinforcing Agent of cis-1,4-Polybutadiene Rubber”

ABSTRACT: Syndiotactic polystyrene (sPS), a thermoplastic polymer characterized by high crystallinity, good chemical resistance and high modulus, has been successfully tested as a reinforcing agent for cis-1,4- polybutadiene (PB) rubber. Blends of sPS and PB have been in situ synthesized using a multistep polymerization process catalyzed by monocyclopentadienyl titanium compounds activated with MAO. This procedure assures an intimate mixing of the components and homogeneous dispersion of the sPS particles having dimension from few hundreds of nanometers to micrometers. The analysis of the mechanical properties of the sPS-PB blends obtained using this process showed enhanced Young’s modulus, toughness, σbreak and ε break: these properties were found to be 1 order of magnitude higher than those of PB and comparable to those of PB charged with inorganic filler as carbon black or silica. A multiblock copolymer (sPSB) comprising segments of sPS and PB was successfully in situ synthesized with the sPS and PB homopolymers and found to be an active compatibilizer of these blends producing a novel semicrystalline phase at the interphase between the sPS particles and the PB matrix

Recognition of zinc transporter 8 and MAP3865c homologous epitopes by Hashimoto's Thyroiditis subjects from Sardinia: a common target with type 1 diabetes?

Mycobacterium avium subspecies paratuberculosis (MAP) asymptomatic infection has been previously linked to Type 1 diabetes (T1D) and Multiple Sclerosis. An association between MAP infection and Hashimoto's thyroiditis (HT) was also proposed only in a case report. This study aimed to investigate the robustness of the latter association, testing a large cohort of HT and healthy control (HCs) subjects, all from Sardinia. Prevalence of anti-MAP3865c Abs was assessed by indirect enzyme-linked immunosorbent assay (ELISA). Moreover, given that human ZnT8 is specifically expressed in the pancreatic β-cells, in the follicle epithelial cells and in the parafollicular cells of the thyroid gland, we also tested ZnT8 epitopes homologues to the MAP3865c immunodominant peptides previously identified. Indeed, Abs targeting MAP3865c and ZnT8 homologous regions display similar frequencies in patients and controls, thus suggesting that Abs recognizing these epitopes could be cross-reactive. A statistically significant difference was found between HT patients and HCs when analyzing the humoral response mounted against MAP3865c/ZnT8 homologues epitopes. To our knowledge, this is the first report, which provides statistically significant evidence sustaining the existence of an association between MAP sero-reactivity and HT. Further studies are required to investigate the relevance of MAP to HT, aimed at deciphering if this pathogen can be at play in triggering this autoimmune disease. Likewise, genetic polymorphism of the host, and other environmental factors need to be investigated

First Record of Anthonomus eugenii (Coleoptera: Curculionidae) in Italy

Summary Anthonomus eugenii Cano (Coleoptera: Curculionidae) was observed for the first time in Italy and the Mediterranean Region attacking sweet pepper (Capsicum annum L.; Solanaceae) in greenhouses and in fields in the coastal area of the Lazio Region of Italy. The incursion, detected in Oct 2013, was a heavy infestation of sweet pepper buds and not fully developed fruits, and causing their premature abscission. The outbreak area was delineated by the coast on the west, and hills on the south and east