An Improved Parameterization for Estimating Effective Atmospheric Emissivity for Use in Calculating Daytime Downwelling Longwave Radiation

Crawford, Todd M.; Duchon, Claude E.

doi:10.1175/1520-0450(1999)038<0474:aipfee>2.0.co;2

Cited by 315 publications

(345 citation statements)

References 20 publications

Supporting

Mentioning

324

Contrasting

Unclassified

Order By: Relevance

“…The use of these locally fitted coefficients led to estimates with MBD values lower than 1% and for RMSD lower than 8%. According to these results, it is clear that the cloudy scheme based on k t presents local dependence, while that proposed by Crawford and Duchon (1999) showed a greater generality. The reason for this could be that in the latter case the formulation, due to the use of a cloud factor based on the normalization of the solar global irradiance to its clear-sky value, takes into account the influence of climatic differences that are lacking in the k t formulation.…”

Section: Parameterisation In K Tmentioning

confidence: 82%

Estimation of downwelling longwave irradiance under all‐sky conditions

Alados

Foyo-Moreno

Alados-Arboledas

2011

Intl Journal of Climatology

View full text Add to dashboard Cite

This work is focused on the characterization and parameterisation of the downward atmospheric irradiance (LW) for clear and cloudy skies. LW is a component of the surface radiation budget that is present throughout the day. Unlike solar irradiance, LW is not measured routinely in extended networks, so it must be estimated indirectly. We evaluated five parameterisations for estimating LW under clear skies. After some consideration regarding the local fitting of the parameterisations, we analysed their different behaviour during day and night and propose a correction model for this effect. We use measurements registered at Tabernas (Spain) from 2001 to 2003. For the locally adjusted parameterisations the root mean square deviation (RMSD) and the mean bias deviation (MBD) are smaller than 5.7 and 0.6%, respectively. The combination of the more complex correction parameterisation of the day/night differences with the locally adjusted formula of Brutsaert and the original formula of Berdalh and Martin leads to estimations with RMSD below 3.1%. Using data registered at Palaiseau (France) the proposed parameterisations yields MBD close to 0% and RMSD below 3.2%. Cloudy conditions were analysed and two different approaches were used to estimate the cloud effect. Both approaches determine all sky LW using a clear-sky formulae and a cloud modification factor, computed with the solar global irradiance on a horizontal surface. The results show that LW can be estimated under all-sky conditions during the daytime with a RMSD of 5.8 and 6.2%, and a MBD of 1.6 and −2.2% for the Crawford and Duchon scheme and the parameterisation in k t , respectively, at Tabernas. The application of the same parameterisations to Palaiseau yields RMSD of 6.7 and 7.7%, and MBD of −2.5 and 0.7%.

show abstract

Section: Parameterisation In K Tmentioning

confidence: 82%

Estimation of downwelling longwave irradiance under all‐sky conditions

Alados

Foyo-Moreno

Alados-Arboledas

2011

Intl Journal of Climatology

View full text Add to dashboard Cite

show abstract

“…For precipitation, a mean number of hours of rain per day was calculated at each site, and this mean duration was used to distribute rainfall regularly over the day. The incoming long-wave radiation was computed at a half-hourly time step from air temperature, air humidity, and incoming short-wave radiation according to Crawford and Duchon [1999].…”

Section: B2 Preparation Of the Climate Forcingmentioning

confidence: 99%

A dynamic global vegetation model for studies of the coupled atmosphere‐biosphere system

Krinner

Viovy

Noblet‐Ducoudré

et al. 2005

Global Biogeochemical Cycles

2,054

2,063

View full text Add to dashboard Cite

[1] This work presents a new dynamic global vegetation model designed as an extension of an existing surface-vegetation-atmosphere transfer scheme which is included in a coupled ocean-atmosphere general circulation model. The new dynamic global vegetation model simulates the principal processes of the continental biosphere influencing the global carbon cycle (photosynthesis, autotrophic and heterotrophic respiration of plants and in soils, fire, etc.) as well as latent, sensible, and kinetic energy exchanges at the surface of soils and plants. As a dynamic vegetation model, it explicitly represents competitive processes such as light competition, sapling establishment, etc. It can thus be used in simulations for the study of feedbacks between transient climate and vegetation cover changes, but it can also be used with a prescribed vegetation distribution. The whole seasonal phenological cycle is prognostically calculated without any prescribed dates or use of satellite data. The model is coupled to the IPSL-CM4 coupled atmosphereocean-vegetation model. Carbon and surface energy fluxes from the coupled hydrologyvegetation model compare well with observations at FluxNet sites. Simulated vegetation distribution and leaf density in a global simulation are evaluated against observations, and carbon stocks and fluxes are compared to available estimates, with satisfying results.

show abstract

“…Missing days of data (defined as having less than 20 hourly measurements during the day) were filled with the median value measured on that yearly Julian day over the entire dataset. Cloud cover was not recorded, and was calculated as a function of the ratio of measured daily average solar radiation to the calculated clear sky radiation value (Environmental and Water Resources Institute, 2005) for that Julian day (Crawford and Duchon, 1999;Yang and others, 2010). Air temperature, wind speed, and relative humidity were measured at both the buoy on the lake and at the meteorological station on the crater rim.…”

Section: Historical Water-quality and Meteorological Data For The Dynmentioning

confidence: 99%

Simulation of deep ventilation in Crater Lake, Oregon, 1951–2099

Wood¹,

Wherry²,

Piccolroaz³

et al. 2016

Scientific Investigations Report

View full text Add to dashboard Cite

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://store.usgs.gov.Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. DatumsVertical coordinate information is referenced to the National Geodetic Vertical Datum of 1929 (NGVD 29).Horizontal coordinate information is referenced to the World Geodetic System of 1984 (WGS 84).Elevation, as used in this report, refers to distance above the vertical datum. Supplemental InformationConcentrations of chemical constituents in water are given in either milligrams per liter (mg/L) or micrograms per liter (µg/L). AbstractThe frequency of deep ventilation events in Crater Lake, a caldera lake in the Oregon Cascade Mountains, was simulated in six future climate scenarios, using a 1-dimensional deep ventilation model (1DDV) that was developed to simulate the ventilation of deep water initiated by reverse stratification and subsequent thermobaric instability. The model was calibrated and validated with lake temperature data collected from 1994 to 2011. Wind and air temperature data from three general circulation models and two representative concentration pathways were used to simulate the change in lake temperature and the frequency of deep ventilation events in possible future climates. The lumped model air2water was used to project lake surface temperature, a required boundary condition for the lake model, based on air temperature in the future climates.The 1DDV model was used to simulate daily water temperature profiles through 2099. All future climate scenarios projected increased water temperature throughout the water column and a substantive reduction in the frequency of deep ventilation events. The least extreme scenario projected the frequency of deep ventilation events to decrease from about 1 in 2 years in current conditions to about 1 in 3 years by 2100. The most extreme scenario considered projected the frequency of deep ventilation events to be about 1 in 7.7 years by 2100. All scenarios predicted that the temperature of the entire water column will be greater than 4 °C for increasing lengths of time in the future and that the conditions required for thermobaric instability induced mixing will become rare or non-existent.The disruption of deep ventilation by itself does not provide a complete picture of the potential ecological and water quality consequences of warming climate to Crater Lake. Estimating the effect of warming climate on deep water oxygen depletion and water clarity will require careful modeling stu...

show abstract

An Improved Parameterization for Estimating Effective Atmospheric Emissivity for Use in Calculating Daytime Downwelling Longwave Radiation

Cited by 315 publications

References 20 publications

Estimation of downwelling longwave irradiance under all‐sky conditions

Estimation of downwelling longwave irradiance under all‐sky conditions

A dynamic global vegetation model for studies of the coupled atmosphere‐biosphere system

Simulation of deep ventilation in Crater Lake, Oregon, 1951–2099

Contact Info

Product

Resources

About