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January 2013: How France Intervened in Mali to Fight Islamist Militants



Statistics on cross-border flows (ie pupils leaving their local authority of residence to attend schools located outside their local authority of residence) were published as additional tables in July 2013.


Abstract. Severe regional haze pollution events occurred in eastern and central China in January 2013, which had adverse effects on the environment and public health. Extremely high levels of particulate matter with aerodynamic diameter of 2.5 μm or less (PM2.5) with dominant components of sulfate and nitrate are responsible for the haze pollution. Although heterogeneous chemistry is thought to play an important role in the production of sulfate and nitrate during haze episodes, few studies have comprehensively evaluated the effect of heterogeneous chemistry on haze formation in China by using the 3-D models due to of a lack of treatments for heterogeneous reactions in most climate and chemical transport models. In this work, the WRF-CMAQ model with newly added heterogeneous reactions is applied to East Asia to evaluate the impacts of heterogeneous chemistry and the meteorological anomaly during January 2013 on regional haze formation. As the parameterization of heterogeneous reactions on different types of particles is not well established yet, we arbitrarily selected the uptake coefficients from reactions on dust particles and then conducted several sensitivity runs to find the value that can best match observations. The revised CMAQ with heterogeneous chemistry not only captures the magnitude and temporal variation of sulfate and nitrate, but also reproduces the enhancement of relative contribution of sulfate and nitrate to PM2.5 mass from clean days to polluted haze days. These results indicate the significant role of heterogeneous chemistry in regional haze formation and improve the understanding of the haze formation mechanisms during the January 2013 episode.




January 2013



The HIPAA Final Rule (138 pages, published January 25, 2013) modified the Privacy, Security, Breach Notification and Enforcement Rules under the Health Insurance Portability and Accountability Act (HIPAA), as amended by the Health Information Technology for Economic and Clinical Health Act (HITECH) and the Genetic Information Nondiscrimination Act (GINA). The Final Rule imposes new obligation on both covered entities (such as group health plans) and business associatios (such as health insurance brokers, consultants, and third-part administrators). Since compliance is generally required by September 23, 2013, affected entities should start undertaking required actions now to ensure they are in compliance by the September deadline.


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The difference between the 0000 UTC 6 Jan 2013 analysis and its corresponding 5-day forecast for (a) 300-hPa geopotential height (100-m contour interval) and (b) 50-hPa geopotential height (50-m contour interval).


The plan of this paper is as follows: section 2 gives a brief description of the GEOS-5 DAS. Section 3a presents the forecast and overview of the January 2013 SSW event. Section 3b discusses the Plumb (1985) three-dimensional wave activity flux formulation and its results during this SSW event. Section 3c shows the Pacific and Atlantic blocking ridges while section 3d presents results of the transient North Atlantic system and section 4 provides a discussion and summary.


The 60N zonal mean of the zonal wind (Fig. 1b) decreases as the 10-hPa polar temperature increases, changing from westerly to easterly at 1200 UTC 6 January. Coupled with the reversed 60N to pole 10-hPa temperature gradient (Fig. 2a) this change in sign of the 10-hPa zonal mean zonal wind determines the time of the SSW event, 1200 UTC 6 January 2013. These winds, after coming close to zero on 10 January, remain easterly until 28 January. The forecasted values of the 10-hPa, 60N, zonal mean zonal wind tracks the analysis, closely following the westerly wind decrease and the change to easterly winds associated with the SSW.


As shown in Coy et al. (2009), rapidly developing upper-tropospheric systems over the North Atlantic appeared to play a role in the forcing of the major SSW events of January 2003 and January 2006. These weather systems developed most rapidly as they moved poleward under the strong stratospheric winds at which time their development extended into the lower stratosphere. To some extent the cold temperatures near the tropopause associated with these systems, and the corresponding lifting of potential temperature surfaces, acted like a moving orographic forcing under the stratospheric jet. Here we investigate a strong tropospheric storm that occurred several days before the major SSW of January 2013.


Unlike the January 2003 and January 2006 major SSW events, this transient upper-tropospheric system is difficult to relate directly to the January 2013 SSW. There is a change in the 10-hPa geopotential heights from 28 December 2012 to 2 January 2013 (the red contour in Figs. 3a and 3d) that suggests an eastward stratospheric wave propagation near 0 coincident with the transient tropospheric development and propagation; however, the large wave-breaking signature is apparent on 28 December, before the transient development in the upper troposphere. This suggests that the transient system, while it may have helped augment the wave breaking, played only a minor role in the January 2013 SSW.


The GEOS-5 five-day forecasts accurately predicted the major SSW of January 2013 (Figs. 1 and 2). In an examination of European Centre of Medium-Range Weather Forecasts (ECMWF) products during the major SSW of 2010, Dörnbrack et al. (2012) showed that forecasting midstratosphere dynamics is most challenging after the SSW, a time when horizontal EPV gradients are small. In spite of an increased spread seen in the ensemble system, Dörnbrack et al. (2012) showed that the high-resolution 5-day ECMWF forecast accurately captured the evolution of the complete 2010 SSW, including the time after the warming. Similarly, the GEOS-5 five-day forecasts at 10 hPa (Fig. 1) are capable of accurately representing the post-SSW dynamics of the lower stratosphere.


Recorded information on this index is available by calling (202) 649-3993. For technical questions on this index, please call David Roderer at (202) 649-3206. The February index value will be announced on March 28, 2013.


Tuesday, Jan. 1, 2013: New Yorkers may have had a dazzling crystal ball to drop at midnight, but that's nothing compared to Saturn. Happy New Year from NASA's Cassini spacecraft and all of us here at SPACE.com! 2ff7e9595c


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