scholarly journals Diurnal Variations of CO2 Mixing Ratio in the Lower Atmosphere by Three Wavelength DIAL

2020 ◽  
Vol 237 ◽  
pp. 03011
Author(s):  
Yasukuni Shibata ◽  
Chikao Nagasawa ◽  
Makoto Abo
Keyword(s):  
Solar Radiation ◽  
Diurnal Variation ◽  
Diurnal Variations ◽  
The Other ◽  
Lower Atmosphere ◽  
Temperature Profiles ◽  
Mixing Ratio ◽  
Other Hand

We have conducted the measurement of high accurate CO2 mixing ratio profiles by measuring the temperature profiles simultaneously using the three wavelength CO2 DIAL. The measurements of CO2 diurnal variation in the lower atmosphere were carried out on sunny and cloudy days respectively. We find out that increasing of the CO2 mixing ratio occurs over the altitude of about 2 km from the surface during nighttime. On the other hand, the CO2 mixing ratio decreases over the lower atmosphere during daytime. In particular, the CO2 mixing ratio decreases earlier on sunny days than on cloudy days after sunrise. This result suggests that CO2 absorption by photosynthesis greatly contributes to the strength of the solar radiation.

scholarly journals Growth and Physiological Characteristics of Lettuce (Lactuca sativa L.) and Rocket (Eruca sativa Mill.) Plants Cultivated under Photovoltaic Panels

2018 ◽  
Vol 46 (1) ◽  
pp. 206-212 ◽  
Author(s):  
Angeliki KAVGA ◽  
Georgios TRYPANAGNOSTOPOULOS ◽  
George ZERVOUDAKIS ◽  
Yiannis TRIPANAGNOSTOPOULOS
Keyword(s):  
Solar Radiation ◽  
Photosynthetic Rate ◽  
Lactuca Sativa ◽  
The Other ◽  
Physiological Characteristics ◽  
Eruca Sativa ◽  
Partial Shading ◽  
Photovoltaic Panels ◽  
Lactuca Sativa L ◽  
Other Hand

Energy demand of greenhouses is an important factor for their economics and photovoltaics can be considered an alternative solution to cover their electrical and heating needs. On the other hand, plants cultivated under different solar radiation intensities usually appear different physiological adaptations. The objective of this research was to investigate the effect of photovoltaic panels’ induced partial shading on growth and physiological characteristics of lettuce (Lactuca sativa L.) and rocket (Eruca sativa Mill.) plants. Our results indicate that lettuce productivity and the corresponding photosynthetic rate were not affected under the photovoltaic cultivation in comparison with the reference one. On the other hand, the rocket cultivation was less productive and showed lower photosynthetic rate under photovoltaic panels than in the reference greenhouse. The different physiological response between lettuce and rocket seems to be associated with the effect of environmental factors such as solar radiation intensity, temperature and humidity apart from the possible inherent characteristics of each plant species.

Diurnal Variation of Pressure and Temperature Aloft in the Eastern Caribbean

1947 ◽  
Vol 28 (7) ◽  
pp. 311-318 ◽  
Author(s):  
Herbert Eiehl
Keyword(s):  
Solar Radiation ◽  
Diurnal Variation ◽  
Temperature Variation ◽  
Diurnal Variations ◽  
Adiabatic Processes ◽  
Convergence And Divergence ◽  
Eastern Caribbean

From three-hourly special radiosonde observations the diurnal pressure and temperature variation is computed for eight levels between the surface and 16 km. The quality of observations is considered, and corrections are applied for the effect of solar radiation on the radiosonde instrument. Both pressure and temperature show large diurnal variations even in the high troposphere. It is suggested that these variations cannot be caused by horizontal convergence and divergence, but must be due to non-adiabatic processes aloft.

Two anisotropies of the cosmic-ray particles producing the cosmic-ray diurnal variation

1968 ◽  
Vol 46 (10) ◽  
pp. S828-S830
Author(s):  
Masatoshi Kitamura
Keyword(s):  
Cosmic Rays ◽  
Diurnal Variation ◽  
Interplanetary Space ◽  
Geomagnetic Latitude ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Low Energy ◽  
The Other ◽  
Energy Spectra ◽  
Cosmic Ray Intensity

The solar diurnal variations of both meson and nucleon components of cosmic rays at sea level at geomagnetic latitude 57.5° and geomagnetic longitude 0° are analyzed by the model in which two anisotropies of cosmic-ray particles (one of them, Δj1, from about 20 h L.T. and the other, Δj2, from about 8 h L.T. in interplanetary space) produce the solar diurnal variation of the cosmic-ray intensity on the earth.When the energy spectra of Δj1 and Δj2 are represented by [Formula: see text] and [Formula: see text], respectively, where j0(E) is the normal energy spectrum of the primary cosmic rays, it is shown that the evaluation for m1 = 1, 2, m2 = 0 and the cutoffs at 8 and 10 BeV on the low-energy side of spectra of both Δj1 and Δj2 agree well with the observational results at Deep River.

scholarly journals Seasonal and diurnal variations of methane and carbon dioxide in the Kathmandu Valley in the foothills of the central Himalaya

2017 ◽  
Author(s):  
Khadak Singh Mahata ◽  
Arnico Kumar Panday ◽  
Maheswar Rupakheti ◽  
Ashish Singh ◽  
Manish Naja ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Monsoon Season ◽  
Winter Season ◽  
Diurnal Variations ◽  
The Other ◽  
Kathmandu Valley ◽  
Mixing Ratio ◽  
Monsoon Period ◽  
Mixing Ratios ◽  
Carbon Dioxide Co2

Abstract. The SusKat-ABC (Sustainable Amosphere for the Kathmandu Valley- Atmospheric Brown Clouds) international air pollution measurement campaign was carried out during December 2012–June 2013 in the Kathmandu Valley and surrounding regions in Nepal. The Kathmandu Valley is a bowl-shaped basin with a severe air pollution problem. This paper reports measurements of two major greenhouse gases (GHGs), methane (CH4) and carbon dioxide (CO2), that begun during the campaign and extended for a year at the SusKat-ABC’s supersite in Bode, a semi-urban location in the Kathmandu Valley. Measurements were also made at a nearby rural site (Chanban), ~ 25 km (aerial distance) to the southwest of Bode, on the other side of a tall ridge. The ambient mixing ratios of methane (CH4), carbon dioxide (CO2), water vapor, and carbon monoxide (CO) were measured with a cavity ring down spectrometer (Picarro G2401, USA), along with meteorological parameters for a year (March 2013–March 2014). Simultaneous measurements were also made at Chanban from 15 July to 3 October 2015. These measurements are the first of their kind in the central Himalayan foothills. At Bode, the annual average mixing ratios of CO2 and CH4 were 419.4 (±23.9) ppm and 2.193 (±0.224) ppm, respectively. These values are higher than the levels observed at background sites such as Mauna Loa, USA (CO2: 396.8 ppm, CH4: 1.831 ppm) and Waliguan, China (CO2: 397.7 ppm, CH4: 1.879 ppm) during the same period, and at other urban/semi-urban sites in the region such as Ahmedabad and Shadnagar (India) and Nanjing (China). They varied slightly across the seasons at Bode, with seasonal average CH4 mixing ratios being 2.157 (±0.230) ppm in the pre-monsoon season, 2.199 (±0.241) ppm in the monsoon, 2.210 (±0.200) ppm in the post-monsoon, and 2.214 (± 0.209) ppm in the winter season. The average CO2 mixing ratios were 426.2 (±25.5) ppm in pre-monsoon, 413.5 (±24.2) ppm in monsoon, 417.3 (±23.1) ppm in post-monsoon, and 421.9 (±20.3) ppm in winter season. The maximum seasonal mean mixing ratio of CH4 in winter was only 0.057 ppm or 2.6 % higher than the seasonal minimum during the pre-monsoon period, while CO2 was 12.8 ppm or 3.1 % higher during the pre-monsoon period (seasonal maximum) than during the monsoon (seasonal minimum). On the other hand, the CO mixing ratio at Bode was 191 % higher during the winter than during the monsoon season. The enhancement in CO2 mixing ratios during the pre-monsoon season is associated with additional CO2 emissions from forest fire and agro-residue burning in northern South Asia in addition to local emissions in the Kathmandu Valley. Published CO / CO2 ratios of different emission sources in Nepal and India were compared with the observed CO / CO2 ratios in this study. This comparison indicated that the major sources in the Kathmandu Valley were residential cooking and vehicle exhaust in all seasons except winter. In winter, the brick kiln emissions were a major source. Simultaneous measurement in Bode and Chanban (15 July–3 Oct 2015) revealed that the mixing ratio of CO2, CH4 and CO mixing ratios were 3.8 %, 12 %, and 64 % higher in Bode than Chanban. Kathmandu Valley, thus, has significant emissions from local sources, which can also be attributed to its bowl shaped geography that is conducive to pollution build-up. All three gas species in Bode showed strong diurnal patterns, whereas CH4 and CO at Chanban did not show any noticeable diurnal variations. These measurements provide the first insights into diurnal and seasonal variation of key greenhouse gases and air pollutants and their local and regional sources, which are important information for the atmospheric research in the region.

AIR-MASS EFFECTS ON TROPOSPHERIC RADIO SCATTER

1964 ◽  
Vol 42 (4) ◽  
pp. 608-615
Author(s):  
Lorne H. Doherty
Keyword(s):  
Diurnal Variation ◽  
The Other ◽  
Propagation Path ◽  
High Signal ◽  
Air Mass ◽  
Mass Effects ◽  
Other Hand ◽  
High Signal Level

Significant differences in signal level and variability on a 2720-Mc/s 90-mile scatter propagation path are shown to be related to the air mass present over the path. Periods of superrefraction are almost always associated with maritime arctic air. Maritime tropical air results in a very stable relatively high signal level. Continental arctic air on the other hand is associated with low signal levels which exhibit a reversed diurnal variation.

DIURNAL CHANGES IN THE CARBOHYDRATES OF WHEAT LEAVES

1943 ◽  
Vol 21c (1) ◽  
pp. 26-40 ◽  
Author(s):  
G. Krotkov
Keyword(s):  
Sugar Content ◽  
Diurnal Variations ◽  
The Other ◽  
Diurnal Changes ◽  
Wheat Leave ◽  
Considerable Decrease ◽  
Other Hand ◽  
Wheat Leaves ◽  
Hydrolysis Of

Data are presented on the diurnal variations in the sugars of wheat leave, as well as on changes in the sugar content of detached and attached leaves, which were taken progressively during the 24 hr. and were starved under the adopted standardized conditions.It was found that in some samples of leaves there was a considerable decrease in their sugars under the conditions of starvation, but on the other hand leaf samples taken either in the first part of a day, or after sunset, usually contained more sugars after starvation than before it. This last observation suggested a considerable hydrolysis of some complex substances in leaves, with the consequent appearance of sugars. From the analysis of the data obtained it was concluded that the observed diurnal variations in the extent of hydrolysis, synthesis, or in translocation of sugars are greatly influenced by the conditions of illumination.

scholarly journals II. On the diurnal variation in the amount of carbon dioxide in the air

1880 ◽  
Vol 30 (200-205) ◽  
pp. 343-355 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Atlantic Ocean ◽  
Diurnal Variation ◽  
Carbonic Acid ◽  
The Other ◽  
Irish Sea ◽  
Large Share ◽  
Diurnal Difference ◽  
Other Hand ◽  
The Irish Sea

Although a large share of attention has been given to the elucidation if the causes which influence the amount of carbonic acid present in he atmosphere during the day, no systematic observations with reference to the relative quantities present in the air of the land during the day and the night appear to have been undertaken since the well known experiments of the younger De Saussure at Chambeisy, upwards of 50 years ago (1820-30), and a similar set by Boussingault at Paris, a few years later, until M. Truchot took up the question in 1873. But the results thus obtained cannot be said to be altogether satisfactory. On the other hand, the question as to the existence of a diurnal variation in the amount of carbonic acid in sea-air may be said to have been fully worked out and set at rest by the careful and extensive set of observations made some years ago by Dr. Thorpe§ on the air of the Irish Sea and Atlantic Ocean. His results went to show that no appreciable diurnal difference exists.

Twenty-two-year revolutions in the cosmic-ray diurnal variations

1968 ◽  
Vol 46 (10) ◽  
pp. S934-S936
Author(s):  
M. Wada ◽  
S. Kudo
Keyword(s):  
Phase Difference ◽  
Geomagnetic Activity ◽  
Radial Flow ◽  
Interplanetary Space ◽  
Cosmic Ray ◽  
Diurnal Variations ◽  
Rigid Rotation ◽  
The Other ◽  
The Sun ◽  
Other Hand

It is shown, from the data obtained during three complete sunspot cycles, that the 22-year variation in the phase of the cosmic-ray diurnal wave is associated with the 11-year revolutions of the diurnal vectors. The revolutions alternate in sense every 11 years. In order to interpret these revolutions, two perpendicular cosmic-ray streamings in interplanetary space are assumed. As both streamings undergo 11-year variations in their velocities, an ellipse is traced out by the termini of the annual vectors; the sense of revolution depends on whether the phase difference between the two is positive or negative. If, on the other hand, their periods are 11 and 22 years and if their phases coincide, the locus is a horseshoelike trajectory, which is traced twice by a to-and-fro motion during 22 years. The observed data available at this stage cannot distinguish between these possibilities. As geomagnetic activity also shows different 11-year variations alternately, its relation to the 22-year revolution in the diurnal variations is discussed. The radial flow of the cosmic-ray particles as well as the rigid rotation of the cosmic-ray gas with the sun suggested by Parker may correspond to the two streamings.

scholarly journals X. Note on the lunar-diurnal variation of magnetic declination

1868 ◽  
Vol 16 ◽  
pp. 59-60
Keyword(s):  
Diurnal Variation ◽  
Royal Society ◽  
Diurnal Variations ◽  
Magnetic Equator ◽  
The Other ◽  
The Sun ◽  
Magnetic Declination ◽  
Royal Society Of London

I received late last night No. 91 of the Proceedings of the Royal Society, and desire to offer the following remarks on the abstract of a paper by Mr. Neumayer which I find therein (vol. xv. p. 414). Mr. Neumayer is evidently unacquainted with the Note by me, read to the Royal Society of London in 1861 (Proc. Roy. Soc. vol. x. p. 475), in which I stated as result of the discussions of five years’ observations at Trevandrum (near the magnetic equator) that the lunar-diurnal variation of magnetic declination became inverted, like the solar-diurnal variation, when the sun passed from one hemisphere to the other, both the solar- and lunar-diurnal variations depending on the position of the sun.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

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