نتایج جستجو برای: troposphere
تعداد نتایج: 5309 فیلتر نتایج به سال:
Air parcels with mixing ratios of high O3 and low H2O (HOLW) are common features in the tropical western Pacific (TWP) mid-troposphere (300-700 hPa). Here, using data collected during aircraft sampling of the TWP in winter 2014, we find strong, positive correlations of O3 with multiple biomass burning tracers in these HOLW structures. Ozone levels in these structures are about a factor of three...
During a series of 8 measurement campaigns within the SPURT project (2001–2003), vertical profiles of CO and O3 have been obtained at subtropical, middle and high latitudes over western Europe, covering the troposphere and lowermost stratosphere up to ∼14 km altitude during all seasons. The seasonal and latitudinal variation of the measured trace gas profiles are compared to simulations with th...
Nitrogen oxides play an important role in the chemistry of earth’s atmosphere. In the troposphere, they provide the only chemical source for ozone, arguably the most important radical in the lower atmosphere. Nitrogen oxides are central in the formation of photochemical smog in the industrialised countries and also in regions with intense biomass burning. In addition to its relevance to troposp...
First-principles simulations suggest that additional OH formation in the troposphere can result from ozone interactions with the surface of cloud droplets. Ozone exhibits an affinity for the air-water interface, which modifies its UV and visible light spectroscopic signatures and photolytic rate constant in the troposphere. Ozone cross sections on the red side of the Hartley band (290- to 350-n...
Via its role in aerosol formation, cosmic ray may affect the global cloudiness and hence climate. Here we show that an increase in cosmic ray fluxes may lead to an increase in particle production in the lower troposphere but a decrease in particle production in the upper troposphere. In addition to the reported positive correlation between cosmic ray variations and low cloudiness, our analysis ...
We show (in confirmation of previous work) using oneand three-dimensional models that extratropical zonal wind anomalies, produced by fluctuating Rossby wave forcing in the troposphere, appear first in the stratosphere, and migrate downward into the troposphere. By systematically eliminating wave reflection and “downward control” through an induced meridional circulation, it is shown that the d...
[1] In this paper, we examine the tropical lower stratosphere and upper troposphere and elucidate the key role of ozone changes in driving temperature trends in this region. We use a radiative fixed dynamical heating model to show that the effects of tropical ozone decreases at 70 hPa and lower pressures can lead to significant cooling not only at stratospheric levels, but also in the ‘‘sub-str...
Recent work has produced a theory for tropical convective available potential energy (CAPE) that highlights the Clausius-Clapeyron (CC) scaling of the atmosphere’s saturation deficit as a driver of increases in CAPE with warming. Here we test this so-called “zero-buoyancy” theory for CAPE by modulating the saturation deficit of cloud-resolving simulations of radiative-convective equilibrium in ...
The role of halogens in both the marine boundary layer and the stratosphere has long been recognized, while their role in the free troposphere is often not considered in global chemical models. However, a careful examination of free-tropospheric chemistry constrained by observations using a full chemical data assimilation system shows that halogens do play a significant role in the free troposp...
The sensitivity of ground-based instruments measuring in the infrared with respect to tropospheric water vapour content is generally limited to the lower and middle troposphere. The large vertical gradients and variabilities avoid a better sensitivity for the upper troposphere/lower stratosphere (UT/LS) region. In this work an optimised retrieval is presented and it is demonstrated that compare...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید