Temperature and humidity profiles in the atmosphere from spaceborne lasers: A feasibility study

Computer simulations of the differential absorption lidar technique in a space craft for the purpose of temperature and humidity profiling indicate: (1) Current technology applied to O2 and H2O lines in the .7 to .8 micrometers wavelength band gives sufficiently high signal-to-noise ratios (up to 50 for a single pulse pair) if backscattering by aerosol particles is high, i.e. profiling accurate to 2 K for temperature and 10% for humidity should be feasible within the turbid lower troposphere in 1 km layers and with an averaging over approximately 100 pulses. (2) The impact of short term fluctuations in aerosol particle concentration is too big for a one laser system. Only a two laser system firing at a time lag of about 1 millisecond can surmount these difficulties. (3) The finite width of the laser line and the quasi-random shift of this line introduce tolerable, partly systematic errors

Long-wavelength gravitational waves and cosmic acceleration

Strong long-scale gravitational waves can explain cosmic acceleration within the context of general relativity without resorting to the assumption of exotic forms of matter such as quintessence. The existence of these gravitational waves in sufficient strength to cause observed acceleration can be compatible with the cosmic microwave background under reasonable physical circumstances. An instance of the Bianchi IX cosmology is demonstrated which also explains the alignment of low-order multipoles observed in the CMB. The model requires a closed cosmology but is otherwise not strongly constrained. Recommendations are made for further observations to verify and better constrain the model.Comment: 80 pages, 2 figure

Irrespective of size, scales, color or body shape, all fish are just fish: object categorization in the gray bamboo shark Chiloscyllium griseum

Object categorization is an important cognitive adaptation, quickly providing an animal with relevant and potentially life-saving information. It can be defined as the process whereby objects that are not the same, are nonetheless grouped together according to some defining feature(s) and responded to as if they were the same. In this way, knowledge about one object, behavior or situation can be extrapolated onto another without much cost and effort. Many vertebrates including humans, monkeys, birds and teleosts have been shown to be able to categorize, with abilities varying between species and tasks. This study assessed object categorization skills in the gray bamboo shark Chiloscyllium griseum. Sharks learned to distinguish between the two categories, 'fish' versus 'snail' independently of image features and image type, i.e., black and white drawings, photographs, comics or negative images. Transfer tests indicated that sharks predominantly focused on and categorized the positive stimulus, while disregarding the negative stimulus

The Law and the “Law”: Two Kinds of Legal Space in Late-Qing China

This article concerns the conceptualization and implementation of a new imaginary of law and geography in nineteenth-century China. In the first half of the nineteenth century, members of the statecraft (jingshi) school of thought adopted an idea of “law” that contrasted codified law with what they conceived of as natural socio-moral norms. That dichotomy explained for them the geographical contraction of Chinese society, the rise of Inner Asian dynasties, and the potential for China to expand once again. The Taiping war provided an opportunity for members of this group to put these ideas into practice by strategically suspending imperial law in favor of official activism in order to bring about more ideal social conditions. From the 1870s onward, this group worked to transform the Inner Asian territory of Xinjiang into a province. That process illustrates the contradictions in this statecraft conception of law.Cet article expose la conceptualisation et la mise en œuvre d’un nouvel imaginaire juridique et géographique dans la Chine du xixe siècle. Dans la première moitié du xixe siècle, des membres de l’école de pensée dite des « sciences de l’État » (jingshi) adoptèrent une conception de la « loi » qui mettait en opposition le droit codifié et ce qu’ils concevaient comme des normes socio-morales naturelles. Cette dichotomie expliquait selon eux la contraction géographique de la société chinoise, l’émergence des dynasties d’Asie centrale, et la possibilité d’une nouvelle expansion chinoise. La guerre des Taiping offrit l’occasion à des membres de ce groupe de mettre ces idées en pratique en suspendant stratégiquement le droit impérial en faveur d’un activisme administratif, de manière à faire avancer leur idéal de relations sociales. À partir des années 1870, ce groupe travailla à transformer le territoire du Xinjiang d’Asie centrale en province de l’empire. Ce processus fait apparaître les contradictions dans la conception que l’école des « sciences de l’État » se faisait du droit.本文關注的是19世紀中國一種關於法律和地理觀念的形成与實踐。19世紀上半葉，經世派思想家認為，“法”（Law）并非是制定法，而是自然的社會道德標準。這样的區别意味著中國社會的地區性收縮、內亞王朝的兴起，以及中國再次擴張的潛能。太平天國戰爭，為他們中的一些成員將這种思想付諸實踐，提供了機會：策略地將帝國法律懸置起來，以支持官方活動，創造更為理想的社會環境。1870年代以降，他們嘗試将內亞的新疆地區改造成一個行省。這一過程顯示了有關國家治理法律觀念的衝突

On the bulk-skin temperature difference and its impact on satellite remote sensing of sea surface temperature

Satellite infrared sensors only observe the temperature of the skin of the ocean rather than the bulk sea surface temperature (SST) traditionally measured from ships and buoys. In order to examine the differences and similarities between skin and bulk temperatures, radiometric measurements of skin temperature were made in the North Atlantic Ocean from a research vessel along with coincident measurements of subsurface bulk temperatures, radiative fluxes, and meteorological variables. Over the entire 6-week data set the bulk-skin temperature differences (AT) range between -1.0 and 1.0 K with mean differences of 0.1 to 0.2 K depending on wind and surface heat flux conditions. The bulk-skin temperature difference varied between day and night (mean differences 0.11 and 0.30 K, respectively) as well as with different cloud conditions, which can mask the horizontal variability of SST in regions of weak horizontal temperature gradients. A coherency analysis reveals strong correlations between skin and bulk temperatures at longer length scales in regions with relatively weak horizontal temperature gradients. The skin-bulk temperature difference is pararneterized in terms of heat and momentum fluxes (or their related variables) with a resulting accuracy of 0.11 K and 0.17 K for night and daytime. A recommendation is made to calibrate satellite derived SST's during night with buoy measurements and the additional aid of meteorological variables to properly handle AT variations