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Dust particles emitted from high latitudes (≥ 50° N and ≥ 40° S, including Arctic as a subregion ≥ 60° N), have a potentially large local, regional, and global significance to climate and environment as short-lived climate forcers, air pollutants and nutrient sources. To understand the multiple impacts of the High Latitude Dust (HLD) on the Earth systems, it is foremost to identify the geographic locations and characteristics of local dust sources. Here, we identify, describe, and quantify the Source Intensity (SI) values using the Global Sand and Dust Storms Source Base Map (G-SDS-SBM), for sixty-four HLD sources included in our collection in the Northern (Alaska, Canada, Denmark, Greenland, Iceland, Svalbard, Sweden, and Russia) and Southern (Antarctica and Patagonia) high latitudes. Activity from most of these HLD dust sources show seasonal character. The environmental and climatic effects of dust on clouds and climatic feedbacks, atmospheric chemistry, marine environment, and cryosphere-atmosphere feedbacks at high latitudes are discussed, and regional-scale modelling of dust atmospheric transport from potential Arctic dust sources is demonstrated. It is estimated that high latitude land area with higher (SI ≥ 0.5), very high (SI ≥ 0.7) and the highest potential (SI ≥ 0.9) for dust emission cover >1 670 000 km2, >560 000 km2, and >240 000 km2, respectively. In the Arctic HLD region, land area with SI ≥ 0.5 is 5.5 % (1 035 059 km2), area with SI ≥ 0.7 is 2.3 % (440 804 km2), and with SI ≥ 0.9 it is 1.1 % (208 701 km2). Minimum SI values in the north HLD region are about three orders of magnitude smaller, indicating that the dust sources of this region are highly dependable on weather conditions. In the south HLD region, soil surface conditions are favourable for dust emission during the whole year. Climate change can cause decrease of snow cover duration, retrieval of glaciers, permafrost thaw, and increase of drought and heat waves intensity and frequency, which all lead to the increasing frequency of topsoil conditions favourable for dust emission and thereby increasing probability for dust storms. Our study provides a step forward to improve the representation of HLD in models and to monitor, quantify and assess the environmental and climate significance of HLD in the future.

SUMMARYThe analysis of atmospheric effects on the radiometric quality of the data, provided by SPOT-1's High Resolution Visible (HR V) sensor in the multispectral mode, was carried out by comparing images with ground measurements synchronized with the passage of the satellite and by using water reflectances as standard reference. The results showed the calibration of reflectances in the image was reliable. In a heterogeneous area, the effect of the environment on the reflectance of a small target due to atmospheric scattering was analyzed and quantified from the radiative transfer model of the Laboratoire d'Optique Atmospherique in Lille, France (model 5S). We showed how the adjacency effect was correlated with lake size and atmospheric turbidity. With this model, we were able to infer from the image a value of the optical thickness of aerosols with a 20 per cent accuracy. Finally, the corrected satellite reflectances of atmospheric effects matched ground measurements with a 10 per cent accuracy.

In England more than in any other country, music has been constantly associated with the performance of stage plays. There is very early evidence of this. In the Miracle Play (1512) the minstrels are asked “to do their diligence” before the prologue and at the end “To give us a daunce.” Shakespeare relied on music to emphasize certain dramatic situations. No fewer than some three hundred times do his stage directions demand the employment of music. I do not speak of references to music on the part of his characters; these are frequent, always correct, and often jocular, but to actual demand for music,—such as “Music plays “—“Soft music within,” and the like. Dr. Naylor in his interesting little work “Shakespeare and Music” declares that such stage directions as these appear no less than forty-one times, music during speeches seven times, and that eighteen times a march is required. Of songs—catches—dirges—trumpets—hautboys, countless examples are to be found in the plays. Very often Shakespeare makes quite subtle distinctions to suit the situation in his directions for music. In “King Lear” there are some interesting examples of this. The first appearance of Lear in regal state is heralded by a Flourish of Trumpets. Later on, in Scene 4, Horns are directed to be played before his entrance. This is no doubt done with a view to denoting his lessened state. He has also just returned from hunting. This shows, I think, that more than a casual thought was given to the matter. Again, in “Lear,” in Act 4, we find the direction “Soft music playing.” Lear is on a bed asleep. That Shakespeare intended the music to continue through the scene and dialogue is evident, as the doctor refers to it in his lines “Louder the music there.” At this point the dramatist no doubt' felt that the beautiful words of Cordelia, “O my dear father ! Restoration, hang thy medicine on my lips,” would be greatly helped by the musical support. The very next scene opens with drums beating and soldiers marching, music very different in character from the “Soft music playing” of the previous scene This I feel sure was not mere accident, and that Shakespeare well knew the value of this contrast which at the same time connects the two scenes.

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