Computing the Solar EUV Irradiance at Wavelengths Below 450 Å
Abstract
The solar EUV irradiance plays a central role in determining the state of the Earth's upper atmosphere. The EUV irradiance at the shortest wavelengths, which is highly variable over time scales from seconds to decades, is particularly important for many aspects of space weather. Systematic spectrally resolved observations at the shortest EUV wavelengths, however, have been rare and there is a need to develop a methodology for estimating and forecasting the solar irradiance at all EUV wavelengths from sparse data sets. The AIA on SDO provides full Sun solar images in 7 narrow EUV wavelength ranges. These channels were selected to provide complete thermal coverage of the corona and allow for calculation of the differential emission measure distribution. In this presentation we report on our efforts to use AIA DEM calculations to estimate the solar EUV irradiance at wavelength below 450 Å, where the emission is predominately optically thin. To validate our AIA DEM calculations we have performed extensive comparisons with simultaneous observations from the EIS instrument on Hinode and find that with the proper constraints we can generally reproduce the results obtained with detailed spectroscopic observations using AIA. We also present comparisons with existing time series of QEUV, the integrated solar irradiance at wavelengths below 450 Å.
- Publication:
-
SDO-3: Exploring the Network of SDO Science
- Pub Date:
- March 2013
- Bibcode:
- 2013enss.confE..47W
- Keywords:
-
- SDO;
- SDO-7;
- SDO 7;
- SDO Workshop;
- 2013 LWS/SDO Science Workshop;
- Solar Dynamic Observatory