Search Results

You are looking at 1 - 10 of 457 items for :

  • Planetary atmospheres x
  • Journal of Atmospheric and Oceanic Technology x
  • User-accessible content x
Clear All
James W. Hannigan, Michael T. Coffey, and Aaron Goldman

1. Introduction Since 1999, regular observations of the infrared (IR) absorption of the atmosphere have been made from a site in Thule, Greenland (76.5°N, 68.8°W, 225 m MSL), by using a solar-viewing Fourier transform interferometer in support of the Network for the Detection of Atmospheric Composition Change (NDACC), formerly the Network for the Detection of Stratospheric Change (NDSC; Kurylo 1991 ; Kurylo and Zander 2000 ). The primary function of the NDACC is to provide directly comparable

Full access
C. Holstein-Rathlou, J. Merrison, J. J. Iversen, A. B. Jakobsen, R. Nicolajsen, P. Nørnberg, K. Rasmussen, A. Merlone, G. Lopardo, T. Hudson, D. Banfield, and G. Portyankina

-Grzebyk et al. 2012 ) aims to promote a metrological approach to the climate and meteorological observations supporting the traceability of measurements involved in climate change—for example, surface and upper-atmosphere measurements of temperature, pressure, humidity, wind speed, and direction. To achieve robustness and reliability of atmospheric measurements, improved calibration procedures and facilities for controlled laboratory observations are needed. In this manuscript a dedicated environmental

Full access
Carol Anne Clayson and Lakshmi Kantha

1. Introduction Enormous effort has been expended over the past few decades to understand and model mixing within the active geophysical boundary layers, the atmospheric boundary layer (ABL) over both land and sea, and the oceanic mixed layer (OML). Mixing in these planetary boundary layers (PBLs) is invariably turbulent, and large eddy simulation (LES; e.g., Moeng and Sullivan 1994 ) and second-moment turbulence closure models (e.g., Mellor and Yamada 1982 ; Kantha 2003 ; Kantha and

Full access
Paul Schmid and Dev Niyogi

1. Introduction The planetary boundary layer (PBL) is the turbulent layer near the earth’s surface. Determining the PBL height is important because it is where any moisture, aerosol, or heat from the surface can be exchanged with the free atmosphere above. It is most commonly observed as an inversion in potential temperature and dewpoint, or as a peak in low-level wind ( Holzworth 1964 ; Grossman and Gamage 1995 ). The top can also be observed from a strong gradient in lidar backscatter

Full access
K. J. Davis, N. Gamage, C. R. Hagelberg, C. Kiemle, D. H. Lenschow, and P. P. Sullivan

wind shear resulted in relatively rapid horizontal dispersion ( Cooper 1994 ). The lidar backscatter image from this flight ( Fig. 2 ) shows the complex, multilayered structure typical of a stable atmosphere. This segment of data was taken about 180 km downwind from the source of the plume. Similar structure is often seen in the nighttime planetary boundary layer over land. The full image ( Fig. 2 ) as well as a single backscatter profile extracted from this dataset ( Fig. 7a ) show the

Full access
Adolfo Comerón, Michaël Sicard, and Francesc Rocadenbosch

1. Introduction The range-resolved backscatter signal of elastic lidars contains information from which the height of aerosol layers can be derived. Identification of these layers is important in atmospheric observations to determine ranges where aerosol properties are likely to be homogeneous, as well as to infer transport phenomena and atmosphere dynamics. A conspicuous example of the latter application is the use of lidar backscatter profiles to measure the planetary boundary layer depth

Full access
Mark A. Broomhall, Leon J. Majewski, Vincent O. Villani, Ian F. Grant, and Steven D. Miller

. (2016) address this by gradually blending in top-of-atmosphere (uncorrected) data at high satellite and solar view zenith angles. This method has been modified here. At the planetary limb, the corrected data are multiplied by a factor, which is linearly decreased from 1.0 to 0.0 over the VZA range of 78° to 88°. This gradually blends the high satellite zenith angle values to that of the background space which replicates the look of the Miller et al. (2016) approach and is easier to implement

Full access
Johannes Bühl, Ronny Engelmann, and Albert Ansmann

the same data acquisition system. The equal detection and data processing of the laser pulse and the atmospheric signal is very important for the deconvolution method explained later. The heterodyne signal is recorded for 100 μ s after the release of the laser pulse, which corresponds to a distance of 15 km in the atmosphere. For one laser shot the data acquisition system records 25 000 data points, which are cut into 200 range gates of 250 data points (1 μ s), each with an overlap of 125 data

Full access
Toshitaka Tsuda, Tatsuhiro Adachi, Yoshihisa Masuda, Shoichiro Fukao, and Susumu Kato

KATORadio Atmospheric Science Center, Kyoto University, Uji, Kyoto, Japan(Manuscript received I April 1992, in final form 13 October 1992)ABSTRACT Applying the RASS (radio acoustic sounding system) technique to the MU (middle and upper atmosphere)radar, profiles of both temperature and wind velocity were observed every 90 s in the height range of about 1.57.0 kin, with a height resolution of 300 m, for about 40 h on 6-8 August 1990. The temperature profiles obtainedwith RASS agreed well with the

Full access
Derek D. Feng and Benjamin M. Herman

, distributed over both land and ocean areas, from 1 to 40 km or more ( Ware et al. 1996 ; Kursinski et al. 1996 , 1997 ; Rocken et al. 1997 ). Studies of planetary atmospheres using radio occultation are by no means new. In fact, radio occultation has been used in probing planetary atmospheres for more than three decades ( Eshleman 1973 ; Tyler 1987 ). The Jet Propulsion Laboratory (JPL) and Stanford University’s radio astronomy group first developed the microwave occultation technique for studying

Full access