还学生一片自由翱翔的天空——探究《沙尘暴》地理活动案例

在地理课堂教学过程中,教师的教学方式怎样改变？在教与学的过程中,教师如何扮演＂组织者、引导者与合作者＂,如何引导学生主动参与、探究、合作？作者结合教学实践,以《沙尘暴》的地理活动为例做了初步分析。

西部农村两代人的命运沧桑——《沙尘暴》

国内首部以沙尘暴为描写背景的长篇小说。宏大的叙述，史诗般的结构，汉赋式的泼墨写意，如大河奔流般地展示了河西走廊半个多的世纪的沧桑巨变和两代人的命运，真实地记录了中国西部农民的生存状态，描述了他们在严酷的自然环境和恶劣的生存困境下。坚忍不拔的进取精神和积极向上的人格力量。通过复杂的矛盾纠葛和波澜壮阔的人生画面的抒写，成功地塑造了以老奎、天旺为代表的新老两代不同性格的农民形象，着力从人性深处挖掘出了由传统农民向现代农民过渡的艰难抉择和人格升华。

沙尘暴

今天早上，我一起床，看见外面的天和往日不一样。天空成了土黄色，西北风鸣鸣叫着，刮着大树摇头晃脑。

沙尘暴的自述

“哈哈……真是天助我也！你们人类也尝尝我的厉害吧，这可是大自然给你们的‘赏赐’，可别怪我不客气，哈哈哈……”

沙尘暴的故事

奇怪！沙尘暴和送纸器有关系吗?或许对绝大多数人来说．它们两者毫无关系。可在二连浩特不同。

沙尘暴的自述

怎样才能和风沙说“拜拜”？ “呼－呼—哈哈！尽情地蔓延吧，遮天盖日，让世界都变成黄色吧！”

Informational digital diagrams applied to predict spring wind,snow,and sandstorms

Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi＇an. Results indicate that, under similar weather circumstances, different events evidently exhibit unique vertical structure features. Informational digital diagrams provide a method for transitional weather prediction, a problem for present extrapolative analysis system.

Features of Sand-dust Deposits in Harbin City,China

From the sedimentologic view, this paper analyses the grain-size distribution and the chemical composition of the deposits from sand-dust storm, occurring in Harbin on March 20, 2002. The result indicates that there exist plentiful coarse matters in the sand-dust deposits in Harbin, and the sand-dust composition presents obvious three peak distribution characteristics, indicating that the sand-dust in Harbin is composed of multi-origin components. The grain-size composition consists of silt （4-8Φ）, accounting for 71.18% of the total, sand （〉4Φ）, 21.70%, and clay （〈8Φ）, only 7.13%. The average grain size （Mz） is 5.14Φ. The chemical elements of the deposits are mainly SiO2 and A1203 and Fe203, totally occupying 77.8%. The enrichment factors （EF） of Mg, K, Si, Fe, Mn, P, Ti, Co, Ni and V elements are all about 1, which mainly come fi＇om lithosphere source, while parts of Cu, Pb, Zn, Cr and Se elements are from pollution sources out of lithosphere source, and As, Cd and Sb elements are mainly from pollution sources. Based on the comprehensive analysis of grain-size, chemical composition, enrichment factor （EF）, discriminant function （DF） and matter source index （PI）, this paper points out that the grain-size distribution and element composition of the sand-dust deposits in Harbin are evidently different from the loess and sand-dust in Lanzhou, and that matter source of the sand-dust in Harbin is different from the loess in Northwest China and the sand-dust in Lanzhon. The sand-dust deposits in Harbin are an admixture of coarse grains transmitted in short distance and fine grains transported in long distance. The plentiful coarse grains of the sand-dust deposits in Harbin origin from sand of local spot, and are the near-souroe deposits transported by low altitude airflow.

Seasonal to interannual prediction of air pollution in China:Review and insight

Complex air pollution problems have resulted in considerable adverse impacts on the environment,human health,and economy in China.However,owing to strict regulations since 2013,the air quality has been greatly improved.Now,the prevention of air pollution has entered a critical stage in combination with climate change mitigation in China.Accurate seasonal to interannual prediction of air pollution(haze,surface 03,and sandstorms) could support the government in planning for air pollution control on an annual basis.Scientists from all over the world have made great progress in understanding climate change and the variability of air pollution and associated physical mechanisms in China,which has provided a scientific basis for the development of climate prediction of air pollution.This paper reviews the progress made in air-pollution climate prediction,and gives some critical insights including update of predictand,change of predictability,and development of coupled model.

PRELIMINARY STUDY ON SAND - DUST STORM DISASTER AND COUNTERMEASURES IN CHINA

As a kind of natural disasters, sand dust storms frequently occur in deserts and their surrounding areas. The occurrence of this disaster in China′s northwest and north China has exerted an extremely adverse effect upon the environment in China. The management of sand dust storms is of a systematic project closely related with the environment such as agriculture, ecosystem, forestry, water conservancy, meteorology and other aspects. Therefore, studies of the formation, the basic features, causes, temporal spatial distribution, developing trend and related disasters of sand dust storms in China are conducted based on satellite data. The experience of sand dust storms control and countermeasures in the United States and some other countries are referred. Meanwhile, preliminary countermeasures relating to sand dust storms in China are proposed.

Correlation of Dust Storms in China with Chlorophyll a Concentration in the Yellow Sea between 1997-2007

Based on daily observation data at 222 meteorological stations in China,the characteristics of dust storms between 1997 and 2007 were examined.Next,the relationship between dust events and chlorophyll (Chl) a concentration in the Yellow Sea was investigated.There were six regions with high annual frequencies of dust storms.The seasonal distribution of dust storms showed spatiotemporal variation.The six regions with highest annual frequencies also exhibited high frequencies of dust storms in spring.Dust storms in most regions occurred in spring.Of all dust storms in China,sixty-five percent of all dust storms occurred during the spring.The area and frequency of dust storms were smaller in fall and winter than in spring and summer.A significant correlation was found between dust events and Chl a concentration in the Yellow Sea.High correlation regions included Qinghai-Xizang region,part of the Hexi Corridor,the western Inner Mongolia and Hetao Regions,and the Hunshandake Desert.The high correlation may be induced by the high ratio of dust storms in the abovementioned regions that arrive over the Yellow Sea,as inferred through a forward trajectory analysis;especially notable is dust transported at a lower altitude (< 3 km).

The digital diagrams analysis and forecast of sandstorm weather

The strong sandstorm weather process analysis has been done with the information digital diagrams method and times extended observation information on 23rd May,2004 in Gansu Province. The research results reveal the unique mechanism structure of sandstorm disaster weather and the signification of irregular information,approve that the region digital diagrams has the capability to forecast the character and intension of transition disaster weather,and explain certainly that the meteorological problem is transformation problem of evolvement science.

A Case Study of a Typical Dust Storm Event over the Loess Plateau of Northwest China

Enhanced observational meteorological elements,energy fluxes,and the concentration of dust aerosols collected from the Semi-Arid Climate Observatory and Laboratory(SACOL) during a typical dust storm period in March 2010 at Lanzhou were used in this paper to investigate the impact of dust aerosols on near surface atmospheric variables and energy budgets.The results show that the entire dust storm event was associated with high wind velocities and decreasing air pressure,and the air changed from cold and wet to warm and dry and then recovered to its initial state.The response of energy fluxes occurred behind meteorological elements.At high dust concentration periods,the net radiation was significantly less in the daytime and higher at night,while the heat fluxes displayed the same trend,indicating the weakening of the land-atmosphere energy exchange.The results can be used to provide verification for numerical model results in semi-arid areas.

Evaluation of Natural Radioactivity in Dust Storms Samples from AI-Najaf//Iraq

Abstract： 40K, 238U and 232Th in dust storms samples from AI-Najaf Holy Area - lraq in year 2013 were measured using a high efficiency gamma ray spectroscopy NaI（Tl） detector. From the measured gamma rays spectra, the specific activity were determined for 40K （range from 237.166 to 368.689 Bq/kg）, 23SU （range from 11.531 to 34.997 Bq/kg） and 232Th （range from 2.805 to 11.162 Bq/kg）. Hazard indices （external hazard index, internal hazard index, radium equivalent activities and absorbed effective dose rates） were calculated for the measured samples to assess the radiation hazards arising from dust storms samples, which is the average of Hazard indices equal （0.214, 0.192, 25.359 nG/y and 50.855 Bq/Kg）, respectively. All results of Hazard indices were compared with safe limit values recommended by UNSCEAR （2008） below the safe limit.

Global influenza in cold phase of Pacific Decade Oscillation

Based on the study of the cold phase of the Pacific Decade Oscillation, pandemic influenza is related to climate. The relation of low temperature, Pacific Decade Oscillation, strongest earthquake, Influenza, hurricane and E1 Nino is researched in this study. In the cold period of Pacific Decade Oscillation, the strongest earthquake, hurricane with La Ni＇na, Pandemic Influenza with E1 Nino will occur stronger and stronger. From 1950 to 1976, the strongest dust-storm is connected with Pandemic Influenza one by one. So, dust-storm is one of factors to spread pandemic influenza viruses.

Effect of Sand and Dust Storms on Microwave Propagation Signals in Southern Libya

The propagation of electromagnetic waves in millimeter band is severely affected by rain, and dust particles in terms of attenuation and de-polarization. The computations of dust and/or sand storms require knowledge of electrical properties of the scattering particles and climate conditions at the studied region. To compute the effect of dust and sand particles on the propagation of electromagnetic waves, it is required to collect the sand particles carried out by the wind, measure the particles size, calculate the concentration, and carry chemical analysis of the contents, then the dielectric constant can be calculated. The main object of this paper is to study the effect of sand and dust storms on wireless communication, such as microwave links, in the southern region of Libya （Sebha, Ashati, Obari, Morzok, Ghat） by determining the attenuation. The result showed that there is some consideration that has to be taken into account in the communication power budget.

短诗三首

沙尘暴 只是一夜之间的事情 沙尘暴最先带来春天的消息 我惊诧于这风的暴动 使白雪陷于风尘

句段亮点

街上的行人特别少，风刮得人都睁不开眼睛，举步艰难，顶风骑车的人就像蜗牛一样，慢吞吞的。

Holocene dust storm variations over northern China:transition from a natural forcing to an anthropogenic forcing

Asian dust storms have long been a major environmental concern in China,affecting the lives of about one billion people.However,it is unclear whether the mechanisms responsible for Asian dust storms during the Holocene varied on different timescales,and thus it is unclear whether there was a shift from a natural forcing to an anthropogenic forcing of dust storms.We reconstructed a high-resolution Holocene record of dust storms from the sediments of an undisturbed alpine lake on the Chinese Loess Plateau.We found that Asian dust storm activity generally increased during the Holocene,with the largest fluctuations occurring during the past 2000 years.The increase in dust storm activity was in contrast to the decrease in East Asian winter monsoon(EAWM)intensity during the Holocene,indicating that the EAWM played a limited role in modulating dust storms.By contrast,the increase in dust storms corresponded to a decrease in East Asian summer monsoon(EASM)precipitation.This demonstrates that EASM precipitation was the dominant control of dust storm activity on a millennial timescale,because decreased EASM precipitation expanded the desert area and thus increased the dust storm activity.The increasing intensity of human activity in the region since the Bronze Age resulted in an acceleration of dust storm activity against the background of decreased EASM precipitation.As human disturbance continued to intensify,beginning at least at~2 cal ka BP,increased dust storms were closely linked to increasing human populations in the dust source regions,and there is a strong temporal coherence between increased dust storms and higher EASM precipitation.This was completely different from when natural processes are dominant.During that period,fewer dust storms occurred during periods of a strengthened EASM.Therefore,there was a shift from a natural forcing to an anthropogenic forcing of dust storms on a multi-decadal to centennial timescale,and was a mode in which‘‘human activity overtook the EASM as the dominant control of the Earth surface system”.