Solar constant

About: Solar constant is a research topic. Over the lifetime, 967 publications have been published within this topic receiving 29647 citations.

The Smithsonian solar constant data revisited: no evidence for cosmic-ray induced aerosol formation in terrestrial insolation data

Abstract: This paper is effectively a technical comment on the paper by Weber in Ann Phys (Berlin). For a long time scientific practice has generally been to publish comments in the same journal as the original paper, to allow comments and corrections (and the courtesy of a reply from the author) to be associated with the first piece of work. Nowadays web linking improves this so readers of a paper cannot be unaware of comments and corrections when C984

Estimating short-term solar variations by a simple envelope matching technique

Abstract: A simple matching technique is explained which allows the computation of the response of the solar surface to perturbations which occur at any depth within the convective envelope of the Sun. This technique was applied to a perturbation of the convective efficiency (alpha-mechanism), and of the non-gas component of the pressure (beta-mechanism) in different regions of the convection zone. The results indicate that either perturbation affects the solar luminosity. However, the alpha-mechanism has little effect in the solar radius, regardless of the location of the perturbed region, whereas the beta-mechanism produces radius changes that become quite large if the location of the perturbed region is deep within the solar convection zone.

The Earth’s climate and variability of the Sun over recent millennia: geophysical, astronomical and archaeological aspects - Introductory remarks

Abstract: The search for periodic or quasi-periodic variations in the solar constant through the analysis of climatic and meterological data has proved elusive. The reason is evident: the atmosphere is a wet gas with much energy stored as latent heat and is in complex interaction dynamically and thermally with the oceans and land areas. This confronts the investigator with a hydrodynamic problem of awesome difficulty and has hitherto frustrated attempts at weather prediction over more than a few days. The instabilities, what we call the weather, cause not only day-to-day but also year-to-year variations so great that many experts have concluded that these would have completely masked possible small changes due to fluctuations of the energy input from the Sun. Yet, as the seasonal changes of solar energy falling on each hemisphere result in such obvious effects, it should not be impossible to detect in the climatic records much smaller changes in the total global input of heat energy into the atmosphere, especially if these are cyclical, by integrating out short-term fluctuations.

An Atmospheric Radiative-Convective Model: Solar Forcings

Abstract: In this Letter, we provide a brief description of a new one-dimensional planetary atmospheric radiative-convective (PARC) model and its responses to solar forcings. To undertake this calculation, we ignore changing lower atmospheric effects and consider only variations in solar energy inputs. The model incorporates the following energies/transport processes: solar visible, IR, and UV radiations; and energy transports by conduction, eddy viscosity, and convection. We note the following changes over previous one-dimensional atmospheric models. (1) Rather than only a global energy balance, a detailed (local) energy balance is employed; thus, radiative and convective energy transports are both calculated explicitly, the latter with mixing-length theory (MLT). (2) The IR opacity of the atmospheric gases is calculated in a self-consistent fashion with the other energy inputs. The model was run with large solar variations sufficient to examine clearly possible solar forcing: variations of 10% in the "solar constant" and 9% in the solar UV. The model exhibits a 6.4 K and a 3 K increase in the lower atmospheric temperatures, respectively, to these forcings. The solar constant influence is similar to other climate models. The model responds significantly, however, to solar UV variations in a new and interesting fashion deserving of further study. The effect may be understood as a result of an elevation of the τ ~ 1 level in the atmosphere associated with the deposition of the UV energy. We suggest some observational tests: as solar activity increases, one would expect (1) the total optical depth of the model atmosphere in the IR to increase and (2) the altitude of the IR radiating region to increase. The model has numerous simplifications that warrant caution, if one were to assume blindly the results applied directly to the real Earth.