12 research outputs found
Finding abnormal events during the Iraq War monitored at Japan 8000km away from Iraq
Department of Earth Sciences, Faculty of Science, Kanazawa UniversityGraduate School of Natural Science and Technology, Kanazawa UniversityMeteorological Research Institute JST Cooperative System for Supporting Priority ResearchMeteorological Research Institute JST Cooperative System for Supporting Priority ResearchGraduate School of Natural Science and Technology, Kanazawa UniversityGraduate School of Natural Science and Technology, Kanazawa UniversityGraduate School of Natural Science and Technology, Kanazawa UniversityUnusual strong acidic rain recorded during the Iraq War in Japan Sea side 8000km away from Iraq. In order to monitor the seasonal change of pH, the rainwater was collected during the period from March 24th to September 24th, 2003 at Kanazawa, Ishikawa Prefecture, Japan. For comparison, the rainwater at Wakayama (the Pacific Ocean side) was collected, during the period from March 24th to April 30th, 2003. The pH, Eh, EC, and DO of the rainwater were measured in laboratory periodically. Filtered rain dusts were investigated by scanning electron microscope equipped with energy dispersive X-ray spectrometer (SEM-EDX), electron probe micro analyzer (EPMA), transmission electron microscope (TEM), energy dispersive X-ray fluorescence spectrometer (ED-XRF), and X-ray powder diffraction (XRD) analyses. In this study, the fluctuation of pH values and electrical conductivity (EC) of rainwater during this half-year period were measured to find abnormal events, such as the Iraq War effects. Since March 21st, 2003, Iraq plunged into the war. The more than 30 oil field fires in Rumaylah, Basrah, Mosul, and other oil fields near the borderline of Kuwait and Iran were reported in March and in April, 2003 in Japan. The first precipitation during the Iraq War was caught on March 24th, 2003. In the period from March 24th to April 5th, the notable low pH value of 3.4-4.4 and high EC value of 20-360ƒハS/cm were detected in Kanazawa. The acidic rain associated with WNW wind (2.7-4.1m/s) has continued to the first 10 days of April in Kanazawa, during the 9 oil fields were burning in Rumaylah, Iraq. In the same time, the upper current of air maps confirmed that the 5520-5700m lines cross over and spread on both Iraq and Japanese Honshu Island. It is considered that westerly wind crossed over both Iraq and Japan. The high EC values from March 24th to April 5th, 2003, suggest that high concentrations of water-soluble carbon particles and soot contained in the rainwater. In addition, the black powdery dusts were detected from the strong acidic rainwater on April 1st. The powdery dusts and carbon-bearing particles contained in the rainwater have characteristics different from that of the Asian aerosol particles (Kosa). The results suggest that both powdery dusts and carbon-bearing particles of rainwater have been produced by combustion of oil field in Iraq. Simulation data support the directly cycling by westerly wind indicating the influence of the Iraq War. Possible evidences provided in this paper, such as strong acidic rain and high EC values with nm-sized carbon soot at lapan Sea side, was the influence of the Iraq War. It was suggested that local events affect the global atmospheric environments. Smoke from oil field fires around Baghdad and other wartime pollution could create long-term health hazards
Operational Dust Prediction
Over the last few years, numerical prediction of dust aerosol concentration has become prominent at several research and operational weather centres due to growing interest from diverse stakeholders, such as solar energy plant managers, health professionals, aviation and military authorities and policymakers. Dust prediction in numerical weather prediction-type models faces a number of challenges owing to the complexity of the system. At the centre of the problem is the vast range of scales required to fully account for all of the physical processes related to dust. Another limiting factor is the paucity of suitable dust observations available for model, evaluation and assimilation. This chapter discusses in detail numerical prediction of dust with examples from systems that are currently providing dust forecasts in near real-time or are part of international efforts to establish daily provision of dust forecasts based on multi-model ensembles. The various models are introduced and described along with an overview on the importance of dust prediction activities and a historical perspective. Assimilation and evaluation aspects in dust prediction are also discussed
Dust cycle: An emerging core theme in Earth system science
The dust cycle is an integral part of the Earth system. Each year, an estimated 2000 Mt dust is emitted into the atmosphere, 75% of which is deposited to the land and 25% to the ocean. The emitted and deposited dust participates in a range physical, chemical and bio-geological processes that interact with the cycles of energy, carbon and water. Dust profoundly affects the energy balance of the Earth system, carries organic material, contributes directly to the carbon cycle and carries iron which is vital to ocean productivity and the ocean-atmosphere CO2 exchange. A deciphering of dust sources, transport and deposition, requires an understanding of the geological controls and climate states – past, present and future. While our knowledge of the dust cycle, its impacts and interactions with the other global-scale bio-geochemical cycles has greatly advanced in the last 30 years, large uncertainties and knowledge gaps still exist. In this review paper, we attempt to provide a benchmark of our present understanding, identify the needs and emphasise the importance of placing the dust issue in the Earth system framework. Our review focuses on (i) the concept of the dust cycle in the context of global biogeochemical cycles; (ii) dust as a climate indicator; (iii) dust modelling; (iv) dust monitoring; and (v) dust parameters. The adoption of a quantitative and global perspective of the dust cycle, underpinned by a deeper understanding of its physical controls, will lead to the reduction of the large uncertainties which presently exist in Earth system models
JRAero: the Japanese Reanalysis for Aerosol v1.0
A global aerosol reanalysis product named the Japanese Reanalysis for Aerosol (JRAero) was constructed by the Meteorological Research Institute (MRI) of the Japan Meteorological Agency. The reanalysis employs a global aerosol transport model developed by MRI and a twodimensional variational data assimilation method. It assimilates maps of aerosol optical depth (AOD) from MODIS onboard the Terra and Aqua satellites every 6 h and has a TL159 horizontal resolution (approximately 1.1°×1.1°). This paper describes the aerosol transport model, the data assimilation system, the observation data, and the setup of the reanalysis and examines its quality with AOD observations. Comparisons with MODIS AODs that were used for the assimilation showed that the reanalysis showed much better agreement than the free run (without assimilation) of the aerosol model and improved under- and overestimation in the free run, thus confirming the accuracy of the data assimilation system. The reanalysis had a root mean square error (RMSE) of 0.05, a correlation coefficient (R) of 0.96, a mean fractional error (MFE) of 23.7 %, a mean fractional bias (MFB) of 2.8 %, and an index of agreement (IOA) of 0.98. The better agreement of the first guess, compared to the free run, indicates that aerosol fields obtained by the reanalysis can improve short-term forecasts. AOD fields from the reanalysis also agreed well with monthly averaged global AODs obtained by the Aerosol Robotic Network (AERONET) (RMSED0.08, R D 0:90, MFED28.1 %, MFBD0.6 %, and IOAD0.93). Site-by-site comparison showed that the reanalysis was considerably better than the free run; RMSE was less than 0.10 at 86.4% of the 181 AERONET sites, R was greater than 0.90 at 40.7% of the sites, and IOA was greater than 0.90 at 43.4% of the sites. However, the reanalysis tended to have a negative bias at urban sites (in particular, megacities in industrializing countries) and a positive bias at mountain sites, possibly because of insufficient anthropogenic emissions data, the coarse model resolution, and the difference in representativeness between satellite and ground-based observations
Dust Vortex in the Taklimakan Desert by Himawari-8 High Frequency and Resolution Observation
The Taklimakan Desert is known to be one of the world’s major sources of aeolian dust particles. Continuous images with 10-min temporal and 2-km spatial resolutions from a new-generation geostationary meteorological satellite captured the lifecycle (generation, evolution and outflow) of a previously unrecognized type of Taklimakan dust storm. The dust storm showed an anti-clockwise spiral structure and a clear core and behaved like a “dust vortex”. From image analysis, the horizontal scale and temporal lifetime of the dust vortex were estimated to be 600 km and 36 hours, respectively. We found that a strong pressure trough (cut-off low), along with a cold air mass located on the northwestern side of the Taklimakan Desert and the high mountains surrounding the Taklimakan Desert, played important roles in the formation and evolution of the dust vortex