Related topics: magnetic field · earth · sun · nasa

Planetary-scale 'heat wave' discovered in Jupiter's atmosphere

An unexpected "heat wave" of 700 degrees Celsius, extending 130,000 kilometers (10 Earth diameters) in Jupiter's atmosphere, has been discovered. James O'Donoghue, of the Japanese Aerospace Exploration Agency (JAXA), has ...

Solar Orbiter solves magnetic switchback mystery

With data from its closest pass of the sun yet, the ESA/NASA Solar Orbiter spacecraft has found compelling clues as to the origin of magnetic switchbacks, and points towards how their physical formation mechanism might help ...

Studying Earth's defenses against solar storms

University of Michigan researchers will play a central role in NASA's upcoming Geospace Dynamics Constellation mission—a first-of-its-kind look at a protective outer layer of Earth's atmosphere and how it interacts with ...

Predicting equatorial plasma bubbles with SWARM

Changes in atmospheric density after sunset can cause hot pockets of gas called "plasma bubbles" to form over the Earth's equator, resulting in communication disruptions between satellites and the Earth. New AI models are ...

Space weather will delay your trains

Fluctuations in space weather are disrupting train signals and causing significant delays. A project investigating the effect of solar storms on railway signals will be presented this week at the National Astronomy Meeting ...

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Solar variation

Solar variations are changes in the amount of solar radiation emitted by the Sun. There are periodic components to these variations, the principal one being the 11-year solar cycle (or sunspot cycle), as well as aperiodic fluctuations. Solar activity has been measured via satellites during recent decades and through 'proxy' variables in prior times. Climate scientists are interested in understanding what, if any, effect variations in solar activity have on the Earth. Effects on the earth caused by solar activity are called "solar forcing".

The variations in total solar irradiance remained at or below the threshold of detectability until the satellite era, although the small fraction in ultra-violet wavelengths varies by a few percent. Total solar output is now measured to vary (over the last three 11-year sunspot cycles) by approximately 0.1% or about 1.3 W/m² peak-to-trough during the 11 year sunspot cycle. The amount of solar radiation received at the outer surface of Earth's atmosphere averages 1,366 watts per square meter (W/m²). There are no direct measurements of the longer-term variation and interpretations of proxy measures of variations differ. On the low side North et al. report results suggesting ~ 0.1% variation over the last 2,000 years. Others suggest the change has been ~ 0.2% increase in solar irradiance just since the 17th century. The combination of solar variation and volcanic effects are likely to have contributed to climate change, for example during the Maunder Minimum. Apart from solar brightness variations, more subtle solar magnetic activity influences on climate from cosmic rays or the Sun's ultraviolet radiation cannot be excluded although confirmation is not at hand since physical models for such effects are still too poorly developed.

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