The application of modified Levenberg-Marquardt method for greenhouse gases retrieval in the Earth's atmosphere from high-resolution IR spectra

2021 ◽  
Author(s):  
Pavel Chistyakov ◽  
Ilya V. Zadvornykh ◽  
Konstantin Gribanov
2020 ◽  
Vol 11 (2) ◽  
pp. 89-95
Author(s):  
Omo Rusdiana ◽  
Syidik Fahmi

Global warming is a gradual increase in the average temperature of the Earth’s atmosphere caused by the increased volumes of greenhouse gases such as carbon dioxide, methane, and nitrous oxide. Greenhouse gases is trapped inside the atmosphere and caused UV radiation difficulty passing through Earth’s atmosphere, a processed is often referred to as the greenhouse effect. Reclamation and revegetation activities were expected could decrease the greenhouse effect. The aims of the research is to estimate total carbon stock in Pine Forest age 2005 or 11 years and 2012 or 4 years, and also to compare the result with former research in post mining revegetation site PT Holcim Indonesia Tbk. Biomass measurement of trees, poles, and saplings is conducted with non-destructive methods meanwhile biomass measurements of understorey, litter, and necromassa used destructive methods. The result showed that the value of biomass and carbon stock on the 2005 pine stand is acquired 75.31 tons/ha and 35.39 tons/ha. The value of the biomass and carbon stock on the 2012 pine stand is acquired 12.72 tons/ha and 5.98 ton/ha or increased from the previous year's measurement. Increasing of biomass content and carbon stocks is caused several factors such as increasing of diameter increment dan site quality. Keywords: biomass, carbon, reclamation


2014 ◽  
Vol 14 (2) ◽  
pp. 255-266 ◽  
Author(s):  
F. Yan ◽  
R. A. E. Fosbury ◽  
M. G. Petr-Gotzens ◽  
G. Zhao ◽  
W. Wang ◽  
...  

AbstractWith the rapid developments in the exoplanet field, more and more terrestrial exoplanets are being detected. Characterizing their atmospheres using transit observations will become a key datum in the quest for detecting an Earth-like exoplanet. The atmospheric transmission spectrum of our Earth will be an ideal template for comparison with future exo-Earth candidates. By observing a lunar eclipse, which offers a similar configuration to that of an exoplanet transit, we have obtained a high-resolution and high signal-to-noise ratio (SNR) transmission spectrum of the Earth's atmosphere. This observation was performed with the High Resolution Spectrograph at Xinglong Station, China during the total lunar eclipse in December 2011. We compare the observed transmission spectrum with our atmospheric model, and determine the characteristics of the various atmospheric species in detail. In the transmission spectrum, O2, O3, O2 · O2, NO2 and H2O are detected, and their column densities are measured and compared with the satellites data. The visible Chappuis band of ozone produces the most prominent absorption feature, which suggests that ozone is a promising molecule for the future exo-Earth characterization. Due to the high resolution and high SNR of our spectrum, several novel details of the Earth atmosphere's transmission spectrum are presented. The individual O2 lines are resolved and O2 isotopes are clearly detected. Our new observations do not confirm the absorption features of Ca II or Na I which have been reported in previous lunar eclipse observations. However, features in these and some other strong Fraunhofer line positions do occur in the observed spectrum. We propose that these are due to a Raman-scattered component in the forward-scattered sunlight appearing in the lunar umbral spectrum. Water vapour absorption is found to be rather weak in our spectrum because the atmosphere we probed is relatively dry, which prompts us to discuss the detectability of water vapour in Earth-like exoplanet atmospheres.


1997 ◽  
Vol 23 (1) ◽  
pp. 149-163

Spatial structures in the solar photosphere are likely to be seen down to scales of the order of the photon mean free path, which is about 70 km in the lower photosphere. This scale corresponds to an angle of O.”1 at disk center. Structures associated with magnetic fields may be expected on even smaller scales. Existing solar telescopes typically have diameters of slightly less than one meter. Hence, even in the visible part of the spectrum, the scales of solar structures extend out to the diffraction limit of current solar telescopes. Therefore, the achievable spatial resolution is limited by turbulence in the Earth’s atmosphere (seeing). This has led to the development of various techniques to overcome this resolution limit and achieve diffraction-limited resolution. This report covers selected highlights and recent work done in the context of high-resolution techniques published in the period from July 1, 1993 to June 30, 1996. Due to the lack of space the report remains necessarily incomplete, and I apologize to all the authors of important contributions that are not cited here. This review does not cover space and balloon-borne instruments that try to achieve high spatial resolution by observing from above the Earth’s atmosphere. Recent work on ground-based high-resolution techniques has been collected in the proceedings of the 13thSacramento Peak Summer Workshop on Real Time and Post Facto Solar Image Correction (Radick 1993).


1977 ◽  
Vol 17 (4) ◽  
pp. 283-291 ◽  
Author(s):  
J.P. Baluteau ◽  
A. Marten ◽  
E. Bussoletti ◽  
M. Anderegg ◽  
J.E. Beckman ◽  
...  

2021 ◽  
Vol 8 (3) ◽  
Author(s):  
Yogendra K. Gautam ◽  
Kavita Sharma ◽  
Shrestha Tyagi ◽  
Anit K. Ambedkar ◽  
Manika Chaudhary ◽  
...  

Climate change and global warming have been two massive concerns for the scientific community during the last few decades. Anthropogenic emissions of greenhouse gases (GHGs) have greatly amplified the level of greenhouse gases in the Earth's atmosphere which results in the gradual heating of the atmosphere. The precise measurement and reliable quantification of GHGs emission in the environment are of the utmost priority for the study of climate change. The detection of GHGs such as carbon dioxide, methane, nitrous oxide and ozone is the first and foremost step in finding the solution to manage and reduce the concentration of these gases in the Earth's atmosphere. The nanostructured metal oxide semiconductor (NMOS) based technologies for sensing GHGs emission have been found most reliable and accurate. Owing to their fascinating structural and morphological properties metal oxide semiconductors become an important class of materials for GHGs emission sensing technology. In this review article, the current concentration of GHGs in the Earth's environment, dominant sources of anthropogenic emissions of these gases and consequently their possible impacts on human life have been described briefly. Further, the different available technologies for GHG sensors along with their principle of operation have been largely discussed. The advantages and disadvantages of each sensor technology have also been highlighted. In particular, this article presents a comprehensive study on the development of various NMOS-based GHGs sensors and their performance analysis in order to establish a strong detection technology for the anthropogenic GHGs. In the last, the scope for improved sensitivity, selectivity and response time for these sensors, their future trends and outlook for researchers are suggested in the conclusion of this article.


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