Air pollution during the 2003 European heat wave as seen by MOZAIC airliners

This study presents an analysis of both MOZAIC profiles above Frankfurt and Lagrangian dispersion model simulations for the 2003 European heat wave. The comparison of MOZAIC measurements in summer 2003 with the 11-year MOZAIC climatology reflects strong temperature anomalies (exceeding 4°C) throughout the lower troposphere. Higher positive anomalies of temperature and negative anomalies of both wind speed and relative humidity are found for the period defined here as the heat wave (2–14 August 2003), compared to the periods before (16–31 July 2003) and after (16–31 August 2003) the heat wave. In addition, Lagrangian model simulations in backward mode indicate the suppressed long-range transport in the mid- to lower troposphere and the enhanced southern origin of air masses for all tropospheric levels during the heat wave. Ozone and carbon monoxide also present strong anomalies (both ~+40 ppbv) during the heat wave, with a maximum vertical extension reaching 6 km altitude around 11 August 2003. Pollution in the planetary boundary layer (PBL) is enhanced during the day, with ozone mixing ratios two times higher than climatological values. This is due to a combination of factors, such as high temperature and radiation, stagnation of air masses and weak dry deposition, which favour the accumulation of ozone precursors and the build-up of ozone. A negligible role of a stratospheric-origin ozone tracer has been found for the lower troposphere in this study. From 29 July to 15 August 2003 forest fires burnt around 0.3×10<sup>6</sup> ha in Portugal and added to atmospheric pollution in Europe. Layers with enhanced CO and NO<sub>y</sub> mixing ratios, advected from Portugal, were crossed by the MOZAIC aircraft in the free troposphere over Frankfurt. A series of forward and backward Lagrangian model simulations have been performed to investigate the origin of anomalies during the whole heat wave. European anthropogenic emissions present the strongest contribution to the measured CO levels in the lower troposphere (near 30%). This source is followed by Portuguese forest fires which affect the lower troposphere after 6 August 2003 and even the PBL around 10 August 2003. The averaged biomass burning contribution reaches 35% during the affected period. Anthropogenic CO of North American origin only marginally influences CO levels over Europe during that period

Iodine nutrition in ewes : effects of low to high iodine intake on iodine content of biological fluids in pregnant and lactating ewes

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Interférence du soufre et du molybdène avec le métabolisme du cuivre et du zinc chez l'agneau

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Iodine nutrition in ewes. 2. Effects of low to high iodine intake by ewes on the I content of biological fluids and plasma immunoglobulins G in newborn lambs

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Comparative effects of selenium supplementation on the plasma selenium concentration and erythrocyte glutathione peroxidase activity in cattle and camels

International audienceAt an experimental farm, five camels and five cows were each given a similar basal diet for 6 months. They received oral trace element supplementation for 3 months (day 22 to 112) which included zinc, copper, selenium, manganese, iodine and cobalt and corresponded to twice the daily requirement generally recommended for cows. Plasma selenium concentrations were significantly lower in the camels (20 (s.e. 2) mg/l) compared with the cows (33 (s.e. 2) mu g/l). The mineral supplementation induced a large increase in the plasma selenium concentration in the camels which reached 200 (s.e. 35) mu g/l. In the cows, the increase was much smaller and did not go beyond 65 (s.e. 8) mu g/l. Before supplementation the red blood cell glutathione peroxidase activity was similar in the camel and the cow varying between 4000 and 6000 IU per 100 g haemoglobin. In both species, this activity increased with mineral supplementation and remained very high even when mineral supplementation was stopped. The results suggested that selenium metabolism in camels is different from that in the cow

Relation comparée entre les concentrations plasmatiques en cuivre/zinc et l'activité de la superoxyde dismutase chez le dromadaire et la vache

2 tables 3 graph.International audienceOn an experimental farm, five camels and five cows were fed with a similar basal diet over a 6-month period. They received an oral trace element supplement for 3 months (days 22-112). This supplement contained zinc and copper sulphate, and corresponded to twice the daily requirement generally recommended for cows. Plasma zinc and copper concentrations were significantly lower in camels (44 micrograms/100 mL for copper and 38 micrograms/100 mL for zinc) than in cows (106 and 83 micrograms/100 mL, respectively). The supplementation had no effect on the plasma zinc concentration in the camels in spite of the low observed values. The mean erythrocyte SOD activity was also significantly higher in the cows (2,404 +/- 211 IU/100 gHb) than in the camels (1,720 +/- 312 IU/100 gHb). In both species, no correlation was found between copper plasma concentration and erythrocyte SOD activity. In cows, a positive relationship was observed between plasma zinc concentration and SOD activity (r = 0.396). In contrast, a negative relationship was found in camels (r = -0.369). These results are discussed in relation to the physiological peculiarities of the camel

Impact of Portugal fires on 2003 European pollution

In 2003, an exceptional heatwave affected Western Europe leading to maximum record temperature breaks in some countries. Stagnant anticyclonic conditions and long sunny periods allowed pollution to reach very high levels. Furthermore devastating forest fires occurred because of hot temperature and drought. For example, in Portugal more than 390000 ha burned which represents 5.6% of the forest surface. The objective of this study is to analyse the impact of long range transport atmospheric pollution during the hot summer 2003 period. We use MOZAIC data from aircraft taking off or landing at Frankfurt, Paris and Vienna. This data set shows pollution which striked Europe in the first half of August 2003. For Frankfurt, between 0 and 2 km heigh, ozone concentration reach 90 ppbv all the 13 days long and the difference with climatology is near + 40 ppbv. This difference rise to an altitude of 6 km the 10 and 11 August. We also see high concentration for carbon monoxide (mean 250 ppbv). Maximas occured the 8, 9 and 10 August in the first kilometre of atmosphere and peaks are visible at high altitude the 4, 5 and 6 August. In order to analyse ozone and precursors evolution we work with the Lagrangian particle dispersion model Flexpart which calculate, forward or backward in time, air particle dispersion by winds. Flexpart allows us to determine air mass origin by identifying ozone precursors emitting region at surface and by analysing particle resident time of retro-plume. The analysis of the 4 August CO peak indicate that the air mass came from Portugal in 4 days and passed some time near the ground. For boundary layer high concentrations, we concentrate our study on air mass contribution from Portugal. About 15% of air crossed by aircraft over Frankfurt under 2 km came from Portugal in 6 to 10 days. It seems that Portugal fires played an important role in the second week of the heat wave when pollution was maximum. This is true for Paris and Vienna even if Paris is nearest the anticylone center. The heatwave has contributed to create high levels in pollutants by its meteorological properties but its consequences like fires played an important role for rising pollutants concentration moreover. [no pdf

Endocrine regulation of calcium and phosphorus concentration in camel's milk

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