Related papers: NLTE solar irradiance modeling with the COSI code
The Earth's primary source of energy is the radiant energy generated by the Sun, which is referred to as solar irradiance, or total solar irradiance (TSI) when all of the radiation is measured. A minor change in the solar irradiance can…
These lectures are intended to present a simple but relatively complete description of the theory needed to understand the formation of lines in non-local thermodynamical equilibrium (NLTE), without appealing to any previous knowledge…
Earth's ionosphere is a perpetual detector of ionizing radiation received from celestial objects, particularly the Sun. Solar ionizing radiation in the form of extreme ultraviolet (EUV) and X-rays during both quiet and active phase of the…
The plasma parameters such as the electron density and temperature plays a key role in the dynamics of the solar atmosphere. These characteristics are important in solar physics, because they can help to understand the physics in the solar…
One of the major tasks in interpretation of data from large-scale stellar surveys is to determine the fundamental atmospheric parameters such as effective temperature, surface gravity, and metallicity. In most on-going and upcoming…
We present results using the AutoClass analysis application available at NASA/Ames Intelligent Systems Div. (2002) which is a Bayesian, finite mixture model classification system developed by Cheeseman and Stutz (1996). We apply this system…
For a "reference day" of minimal solar activity between cycles 23 and 24 we compute the brightness temperature from solar spectral irradiance for each wavelength. We consider small variations of irradiance and temperature about the…
The attribution of part of global warming to changes in the total solar irradiance (TSI) is an important topic which is not, yet, fully understood. Here, we examine the TSI induced temperature (T) changes on a variety of time scales, from…
Precise numerical standard solar models (SSMs) now agree with one another and with helioseismological observations in the convective and outer radiative zones. Nevertheless these models obscure how luminosity, neutrino production and g-mode…
The oscillations of climatic parameters of North Atlantic Ocean play important role in various events in North America and Europe. Several climatic indices are associated with these oscillations. The long term Atlantic temperature anomalies…
Motivated by the solar composition problem and by using the recently developed Linear Solar Model approach, we analyze the role of opacity and metals in the sun. After a brief discussion of the relation between the effects produced by a…
The Northern Sky Variability Survey (NSVS) is a temporal record of the sky over the optical magnitude range from 8 to 15.5. It was conducted in the course of the first generation Robotic Optical Transient Search Experiment (ROTSE-I) using a…
Our recent re-analysis of the solar photospheric spectra with non-local thermodynamic equilibrium (non-LTE) models resulted in higher metal abundances compared to previous works. When applying the new chemical abundances to Standard Solar…
The Ca II H line is one of the strongest lines in the solar spectrum and provides continuous information on the solar atmosphere from the photosphere to the lower chromosphere. We describe an inversion approach that reproduces observed Ca…
The solar contribution to global mean air surface temperature change is analyzed by using an empirical bi-scale climate model characterized by both fast and slow characteristic time responses to solar forcing: $\tau_1 =0.4 \pm 0.1$ yr, and…
The latest solar atmosphere models include non-LTE corrections and 3D hydrodynamic convection simulations. These models predict a significant reduction in the solar metal abundance, which leads to a serious conflict between helioseismic…
Both composition and temperature play a crucial role in determining the NO radiative cooling in lower thermosphere as observed by TIMED/SABER. In this work, we present a detailed investigation of seasonal variation in thermospheric NO…
The energy balance for an atmospheric layer near the soil is evaluated. By integrating it over the whole day period a linear relationship between the global daily solar radiation incident on a horizontal surface and the product of the…
Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the…
The dynamics of the solar radiative interior are still poorly constrained by comparison to the convective zone. This disparity is even more marked when we attempt to derive meaningful temporal variations. Many data sets contain a small…