On the basis of an asymmetric, conjugated, partially or wholly deprotonated 5-(pyridin-3-yl)-1H-pyrazole-3-carboxylic acid (H 2 ppc),, and [Co(Hppc) 2 (mbbbm)] 2 (5) [mbbbm = 1,3-bis(benzimidazole-1-ylmethyl)benzene)] have been synthesized and characterized magnetically and structurally. Polymer 1, which has the Schlafi symbol (4 2 •6 2 •8 2 ) 2 (4 2 •6•8 3 ) 2 , is a three-dimensional (3D) network. Polymer 2 includes a mononuclear subunit and an infinite two-dimensional (2D) framework subunit, while polymer 3 is a 2D sheet structure. Polymer 4 is characterized by a one-dimensional double ladder-like chain structure. Complex 5 possesses a binuclear structure. Magnetization data for 1 with the Co 2 units show the antiferromagnetic coupling in the Co 2 units. No long-range magnetic ordering is observed for 1. 2, 3, and 5 display weak antiferromagnetic exchange interactions. For 4 with the similar Co 2 units, it also exhibits antiferromagnetic coupling in the Co 2 units, and the M(H) curve is consistent with the antiferromagnetic nature in the Co 2 units. Variable temperature magnetic studies reveal that 2, 3, and 5 display weak antiferromagnetic interactions. The observed magnetization values, which were ∼2.5 Nβ at high field for 2, 3, and 5, are in accordance with the value anticipated for single uncompensated S = 1/2 spin.

In this study, two pattern projection methods, i.e., the Stepwise Pattern Projection Method (SPPM) and the newly proposed Neighborhood Pattern Projection Method (NPPM), are investigated to improve forecast skills of daily maximum and minimum temperatures (Tmax and Tmin) over East Asia with lead times of 1–7 days. Meanwhile, the decaying averaging method (DAM) is conducted in parallel for comparison. These post-processing methods are found to effectively calibrate the temperature forecasts on the basis of the raw ECMWF output. Generally, the SPPM is slightly inferior to the DAM, while its insufficiency decreases with increasing lead times. The NPPM shows manifest superiority for all lead times, with the mean absolute errors of Tmax and Tmin decreased by ~0.7°C and ~0.9°C, respectively. Advantages of the two pattern projection methods are both mainly concentrated on the high-altitude areas such as the Tibetan Plateau, where the raw ECMWF forecasts show most conspicuous biases. In addition, aiming at further assessments of these methods on extreme event forecasts, two case experiments are carried out towards a heat wave and a cold surge, respectively. The NPPM is retained as the optimal with the highest forecast skills, which reduces most of the biases to < 2°.C for both Tmax and Tmin over all the lead days. In general, the statistical pattern projection methods are capable of effectively eliminating spatial biases in forecasts of surface air temperature. Compared with the initial SPPM, the NPPM not only produces more powerful forecast calibrations, but also provides more pragmatic calculations and greater potential economic benefits in practical applications.

Changes of surface air temperature (SAT) over the Indochina Peninsula (ICP) under the Representative Concentration Pathway (RCP) 8.5 scenario are projected for wet and dry seasons in the short-term (2020-2049) and long-term (2070-2099) future of the twenty-first century. A first analysis on projections of the SAT by the state-of-the-art regionally coupled atmosphere-ocean model ROM, including exchanges of momentum, heat, and water fluxes between the atmosphere (Regional Model) and ocean (Max Planck Institute Ocean Model) models, shows the following results: (i) In both seasons, the highest SAT occurs over the southern coastal area while the lowest over the northern mountains. The highest warming magnitudes are located in the northwestern part of the ICP. The regionally averaged SAT over the ICP increases by 2.61°C in the wet season from short-to long-term future, which is slightly faster than that of 2.50°C in the dry season. (ii) During the short-term future, largest SAT trends occur over the southeast and northwest ICP in wet and dry seasons, respectively. On regional average, the wet season is characterized by a significant warming rate of 0.22°C decade −1 , while it is non-significant with 0.11°C decade −1 for the dry season. For the long-term future, the rapid warming is strengthened significantly over whole ICP, with trends of 0.51°C decade −1 and 0.42°C decade −1 in wet and dry seasons, respectively. (iii) In the long-term future, more conspicuous warming is noted, especially in the wet season, due to the increased downward longwave radiation. Higher CO 2 concentrations enhancing the greenhouse effect can be attributed to the water vaporgreenhouse feedback, which, affecting atmospheric humidity and counter radiation, leads to the rising SAT.

This study investigates eastward-moving summer heavy rainfall events in the lower reaches of the Yangtze River (LRYR), which are associated with the Tibetan Plateau (TP) vortices. On the basis of rainfall data from gauges and additional atmospheric data from the ERA-Interim reanalysis, the dynamic and thermodynamic effects of moisture transport and diabatic heating are estimated to determine the physical mechanisms that support the eastward-moving heavy rainfall events. As the rain band moves eastward, it is accompanied by anomalous cyclonic circulation in the upper and middle troposphere and enhanced vertical motion throughout the troposphere. In particular, the rainfall region is located in the forehead of the upper-level trough which is ideal for baroclinic organization of the convective system and further development of the eastward-moving vortex. The large atmospheric apparent heat source (Q1) also contributes for lifting the lower-level air into the upper atmosphere and for enhancing the low-level convective motion and convergence during the heavy rainfall process. Piecewise potential vorticity inversion further verifies the crucial role that the diabatic heating played in developing the anomalous geopotential height favorable for the enhanced rainfall. The combined action of the dynamic and thermodynamic processes, as well as the rich moisture supply from the seas, synergistically sustained and enhanced the eastward-moving rainfall.

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