Sentences with phrase «term changes in solar activity»

The authors «show that the index commonly used for quantifying long - term changes in solar activity, the sunspot number, accounts for only one part of solar activity and using this index leads to the underestimation of the role of solar activity in the global warming in the recent decades.

«Once again about global warming and solar activity We show that the index commonly used for quantifying long - term changes in solar activity, the sunspot number, accounts for only one part of solar activity and using this index leads to the underestimation of the role of solar activity in the global warming in the recent decades.

We show that the index commonly used for quantifying long - term changes in solar activity, the sunspot number, accounts for only one part of solar activity (William: Closed magnetic field) and using this index leads to the underestimation of the role of solar activity in the global warming in the recent decades.

Sunspot observations (going back to the 17th century), as well as data from isotopes generated by cosmic radiation, provide evidence for longer - term changes in solar activity.

Solar cycle length is a useful indicator of long term changes in solar activity.

One repeats the last 11 - year solar cycle until 2100 (eg - no long term change in solar activity).

The smoothness of the change at Mauna Loa could be a result of the most dominant process being a longer term change in solar activity levels such as from LIA to date.

Not exact matches

If that holds (directly or indirectly) for longer term changes (in this case continuous higher levels) of solar activity remains to be proven.

The red line incorporates natural influences like changes in solar output and volcanic activity but virtually all of the long - term warming is attributable to human - caused increases in greenhouse gasses.

It seems that in terms of the total amount of energy coming from the sun there is only a very small variation due to the changing level of solar activity during a single cycle.

Henrik Svensmark and others have shown a long - term correlation between solar activity and global temperature and have hypothesized that this results from changes in galactic cosmic rays leading to changes in cloud cover.

12 * ICE AGES: More elliptical orbit causes less sunlight to reach Earth — results in ice ages (100,000 yr cycles) * VOLCANIC ACTIVITY: Release ash and aerosols into the atmosphere Reflects sun rays causing cooler temps * SOLAR ENERGY: Cause short term changes Less solar energy can cause small iceSOLAR ENERGY: Cause short term changes Less solar energy can cause small icesolar energy can cause small ice ages

A shift in atmospheric circulation in response to changes in solar activity is broadly consistent with atmospheric circulation patterns in long - term climate model simulations, and in reanalysis data that assimilate observations from recent solar minima into a climate model.

Longer term indicators of solar activity show changes over millennia that mirror the state of upwelling in the Pacific.

Long - term trends in the upper atmosphere - ionosphere are a complex problem due to simultaneous presence of several drivers of trends, which behave in a different way: increasing atmospheric concentration of greenhouse gases, mainly CO2, long - term changes of geomagnetic and solar activity, secular change of the Earth's main magnetic field, remarkable long - term changes of stratospheric ozone concentration, and very probably long - term changes of atmospheric dynamics, particularly of atmospheric wave activity (Lastovicka 2009; Qian et al. 2011; Lastovicka et al. 2012).

Quasi-27-day periodicity is a typical medium - term response of the neutral atmosphere and ionosphere to the changes in solar and geomagnetic activity.

Long - term trends and changes (longer than solar cycle) can partly be caused by long - term changes of trend drivers of solar / space weather origin like geomagnetic activity, which in terms of the aa - index was increasing over almost the whole 20th century (e.g., Mursula & Martini 2006), even though now it is low.

Section 1 contains five subsections with results on 27 - day response of low - latitude ionosphere to solar extreme - ultraviolet (EUV) radiation, response to the recurrent geomagnetic storms, long - term trends in the upper atmosphere, latitudinal dependence of total electron content on EUV changes, and statistical analysis of ionospheric behavior during prolonged period of solar activity.

The former is the result of internal variability and radiative forcing (solar output and volcanic activity) rather than long - term changes in Earth's orbital geometry.

There is a solid body of research now showing that any apparent slow - down of warming during the past decade was likely due to natural short - term factors (like small changes in solar output and volcanic activity) and internal fluctuations related to e.g. the El Niño phenomenon.

The research appears to indicate that the short - term fluctuations in solar activity, though they discernibly cause the short - term cycles global temperatures in a manner that the monotonic increase in CO2 manifestly does not, are absolutely predictive of global temperature change on all timescales provided that the time - integral of the solar - activity change is taken.

http://www.agci.org/docs/lean.pdf «Global (and regional) surface temperature fluctuations in the past 120 years reflect, as in the space era, a combination of solar, volcanic, ENSO, and anthropogenic influences, with relative contributions shown in Figure 6.22 The adopted solar brightness changes in this scenario are based on a solar surface flux transport model; although long - term changes are «50 % larger than the 11 - year irradiance cycle, they are significantly smaller than the original estimates based on variations in Sun - like stars and geomagnetic activity.

Since such models can not account for the climate system's apparent sensitivity to small perturbations in solar energy apparently brought about by the very long term changes in the Earth's orbit about the Sun, they may also underestimate climate sensitivity to energy output fluctuations caused by solar activity, even during the eleven - year Schwabe cycle.

If greater changes in solar radiation occur — as seems probable based on what is known of climate and solar activity in the past — the Sun needs to be considered in long - term climate projections.

We know that there are significant changes of much longer term in the overall level of solar activity.

It seems likely that changes in solar radiation, linked to long - term variations in solar activity, may have been the dominant climate driver in the period between about AD 1600 and 1850.

Solar irradiance measurements from 1978 to 2013 will have sampled only three 11 - year irradiance cycles, which alone is insufficient time to determine whether long - term irradiance trends occur or to quantify the broad range of irradiance changes possible in activity cycles of varying strength.

They also concluded that long - term changes in monsoon patterns were more likely due to variations in solar activity than rising global temperatures.

The term «radiative forcing» refers to a global energy imbalance on Earth, which may be caused by various effects like changes in the greenhouse effect or solar activity.