The effects of a solar eclipse on photo-oxidants in different areas of China

Wu, Jianbin; Wang, Z. F.; Zhang, W.; Dong, Huabin; Pan, Xiaole; Li, J.; Lin, Chuan-Yao; Xie, Pinhua

doi:10.5194/acp-11-8075-2011

Cited by 5 publications

(10 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, PAY and XIA show the largest delays with similar variations. In the first case, the minimum value is reached 1 h and 16 min after the MOT with an anomaly of −1.1 K. In the second case, the minimum temperature is shown with a shift of 11 min and a variation in −1.2 K. Wu et al (2011) reported similar temperature decreases during the same solar eclipse over China using the WRF-CHEM module. The amplitude of the temperature decrease in TAM is also in agreement with the WRF simulations in Greece shown by Founda et al (2007).…”

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5957supporting

confidence: 52%

“…6) linked to high nonlinear relationships between the model dynamics and physical schemes. The particular variations in wind speed and direction during and after the eclipse are related to the degree of obscuration as well as the local environment and meteorological patterns, as it has been presented in other previous studies (Fernández et al, 1993b;Founda et al, 2007;Wu et al, 2011).…”

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5957mentioning

confidence: 88%

“…Related to the Weather Research and Forecasting-Advanced Research WRF (WRF-ARW) model, Founda et al (2007) parameterized the eclipse of 29 March 2006 assuming a variation in the solar constant proportional to the distance from the shadow axis, considered as a point moving on Earth with a specific velocity. More recently, Wu et al (2011) used the WRF-ARW coupled with the WRF-CHEM module for analyzing the sensitivity of the tropospheric ozone and other chemical species as well as the effects on meteorological variables to the limb darkening effect as well as the effects on meteorological and other chemical species during the eclipse of 22 July 2009 over China. The solar eclipse effect was added, modifying the solar radiation and photolysis rates using a scaling factor as a function of the latitude, longitude, time and wavelength.…”

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5951mentioning

confidence: 99%

See 2 more Smart Citations

Implementation of Bessel's method for solar eclipses prediction in the WRF-ARW model

Montornès

Codina

Zack³

et al. 2016

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. Solar eclipses are predictable astronomical events that abruptly reduce the incoming solar radiation into the Earth's atmosphere, which frequently results in nonnegligible changes in meteorological fields. The meteorological impacts of these events have been analyzed in many studies since the late 1960s. The recent growth in the solar energy industry has greatly increased the interest in providing more detail in the modeling of solar radiation variations in numerical weather prediction (NWP) models for the use in solar resource assessment and forecasting applications. The significant impact of the recent partial and total solar eclipses that occurred in the USA (23 October 2014) and Europe (20 March 2015) on solar power generation have provided additional motivation and interest for including these astronomical events in the current solar parameterizations.Although some studies added solar eclipse episodes within NWP codes in the 1990s and 2000s, they used eclipse parameterizations designed for a particular case study. In contrast to these earlier implementations, this paper documents a new package for the Weather Research and ForecastingAdvanced Research WRF (WRF-ARW) model that can simulate any partial, total or hybrid solar eclipse for the period 1950 to 2050 and is also extensible to a longer period. The algorithm analytically computes the trajectory of the Moon's shadow and the degree of obscuration of the solar disk at each grid point of the domain based on Bessel's method and the Five Millennium Catalog of Solar Eclipses provided by NASA, with a negligible computational time. Then, the incoming radiation is modified accordingly at each grid point of the domain.This contribution is divided in three parts. First, the implementation of Bessel's method is validated for solar eclipses in the period 1950-2050, by comparing the shadow trajectory with values provided by NASA. Latitude and longitude are determined with a bias lower than 5 × 10 −3 degrees (i.e., ∼ 550 m at the Equator) and are slightly overestimated and underestimated, respectively. The second part includes a validation of the simulated global horizontal irradiance (GHI) for four total solar eclipses with measurements from the Baseline Surface Radiation Network (BSRN). The results show an improvement in mean absolute error (MAE) from 77 to 90 % under cloudless skies. Lower agreement between modeled and measured GHI is observed under cloudy conditions because the effect of clouds is not included in the simulations for a better analysis of the eclipse outcomes. Finally, an introductory discussion of eclipse-induced perturbations in the surface meteorological fields (e.g., temperature, wind speed) is provided by comparing the WRF-eclipse outcomes with control simulations.

show abstract

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5957supporting

confidence: 52%

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5957mentioning

confidence: 88%

Section: A Montornès Et Al: Solar Eclipses In Wrf-arw Model 5951mentioning

confidence: 99%

See 1 more Smart Citation

Implementation of Bessel's method for solar eclipses prediction in the WRF-ARW model

Montornès

Codina

Zack³

et al. 2016

Atmos. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Other previous work has found that the degree of O 3 loss during the eclipse is also a function of the O 3 /NO x ratio. Comparing data from polluted and clean sites, Wu et al (2011) found larger O 3 loss rates and higher NO 2 enhancements in polluted areas. Similar conclusions were derived in a comparison of eclipse data from four sites in Greece.…”

Section: Factors Driving the Trace Gas Behavior On The Eclipse Daymentioning

confidence: 88%

Contrasting behavior of slow and fast photoreactive gases during the August 21, 2017, solar eclipse

Helmig

Blanchard

Hueber

2018

Elementa: Science of the Anthropocene

View full text Add to dashboard Cite

The total solar eclipse on August 21, 2017, provided a rare opportunity to observe and test our understanding of atmospheric dynamics and photochemical dependency on solar irradiance. Here, we utilize observations from the continuous monitoring of both inert and photoreactive trace gases near Boulder, Colorado, for contrasting the unique dynamic and photochemical forcings on the eclipse day. The monitoring station saw a 93% solar obstruction during the peak of the eclipse. Eclipse day data are contrasted with the full month's record from this site. The loss of irradiance caused cooling of the surface air by ~3oC, and weakened convective and tur-bulent mixing. This resulted in a buildup of non-reactive gases (methane, volatile organic com-pounds) as well as nitrogen oxides (NO, NO2) in the surface layer. In contrast, ozone (O3) de-clined by ~15 ppb during the first part of the eclipse compared to median August diurnal mixing ratios. Similar O3 signatures were observed at a series of network stations along the Northern Colorado Front Range. With the loss of irradiance, the initial ratio of NO/(NO+NO2) of ~0.2 dropped steadily, bottoming out at <0.01, but rebounded to ~50% above average levels towards the end of the eclipse. Above average O3 enhancements were seen in the afternoon hours fol-lowing the eclipse. The contrasting behavior of reactive and non-reactive gases, and compari-son with other published eclipse data, allow characterizing these responses as urban/polluted behavior.

show abstract

“…In previous works where the reduction of the incoming shortwave solar radiation, during solar eclipses, has been deemed as input for calculations, researchers apply the so‐called obscuration function, which takes into consideration the solar limb darkening effect (e.g., Eckermann et al, ; Hunt, ; Koepke et al, ; Outcalt & Meisel, ; Phillips, ; Svensson, ; Tzanis, ; Wu et al, ); others, however, have preferred using the occultation function, which focuses on only geometrical aspects (astrometric) of the solar disk's blocking, meaning that there is no limb darkening (e.g., Aplin & Harrison, ; Jagannathan et al, ; Korlarž et al, ; Vogel et al, ). The solar radiation differs from that of a hypothetical Sun without limb darkening up to around 50% at the 550‐nm wavelength according to Koepke et al ().…”

Section: The Occultation and Obscuration Functionsmentioning

confidence: 99%

Cloudiness and Solar Radiation During the Longest Total Solar Eclipse of the 21st Century at Tianhuangping (Zhejiang), China

Peñaloza-Murillo

Pasachoff

2018

JGR Atmospheres

View full text Add to dashboard Cite

The lack of comprehensive solar radiation monitoring during the longest total solar eclipse of the 21st century at Tianhuangping (Zhejiang), China, on 22 July 2009, has led to this investigation in order to evaluate the cloudiness contribution in estimating the impact on global solar radiation throughout this phenomenon. In doing so, we applied a cloud cover empirical model to obtain the global solar radiation and, at the same time, we deduced a theoretical model to get the direct solar radiation in which both the occultation and obscuration functions of this eclipse are included. We took limb darkening and atmospheric transmission into account. Though the weather during our eclipse observations agreed with the forecasts for that day, clouds and some rain, we were nonetheless able to observe all phases of the eclipse from our observation site at Tianhuangping. This experience suggests that for coming eclipses a record of the in situ observation protocol of cloudiness is mandatory. Our results for comparing global solar radiation models indicate that our total solar eclipse radiation model is quite acceptable and representative of that which could have happened at that time.Plain Language Summary A total solar eclipse is a situation where the Sun is obscured by the Moon viewed from Earth. In this particular arrangement in space a shadow is cast over a particular region. Thus, the ideal circumstances to observe a total solar eclipse are those in which the sky is cloudless in that region or zone. Yet from time to time this phenomenon occurs in the presence of interfering clouds preventing a direct observation of the event. However, under these adverse circumstances effects over the environment can still be felt and measured as, for example, the rapid reduction of solar energy reaching the surface. In that case such measurements would be lacking, but with some information about cloudiness one can have an idea of how the variation of this energy during the eclipse took place. In the procedure a quantitative knowledge of how the Moon disk is going to progressively cut the Sun's brightness during the eclipse is necessary. From an environmental point of view it is shown that a scientific observation of a total solar eclipse matters even though it was made under the influence of blocking clouds.

show abstract

The effects of a solar eclipse on photo-oxidants in different areas of China

Cited by 5 publications

References 35 publications

Implementation of Bessel's method for solar eclipses prediction in the WRF-ARW model

Implementation of Bessel's method for solar eclipses prediction in the WRF-ARW model

Contrasting behavior of slow and fast photoreactive gases during the August 21, 2017, solar eclipse

Cloudiness and Solar Radiation During the Longest Total Solar Eclipse of the 21st Century at Tianhuangping (Zhejiang), China

Contact Info

Product

Resources

About