Sentences with phrase «solar irradiance variation»

The amplitude of the solar irradiance variation is smaller than the planetary energy

It misses the point when it comes to the earth's climate's non-linear response to solar irradiance variation for example, though.

re # 6 I agree with you, Alastair, if [deltaT] 2xCO2 is 3 °C, 0,5 °C from solar irradiance variation doesn't matter.

The «equilibrium» sensitivity of the global surface temperature to solar irradiance variations, which is calculated simply by dividing the absolute temperature on the earth's surface (288K) by the solar constant (1365Wm - 2), is based on the assumption that the climate response is linear in the whole temperature band starting at the zero point.

As examples of work in this category, I would mention Judith Lean's tireless efforts on relating luminosity to sunspot number, the work of Bard and colleagues on developing isotopic solar proxies like 10Be, Shindell's work on response to solar ultraviolet variability, and the work of Foukal et al on factors governing solar irradiance variations.

Let's set the stage by noting that, as a significant competitor to anthropogenic greenhouse forcing of recent climate change, the direct radiative forcing by solar irradiance variations is dead on arrival.

Solar irradiance variations are sometimes assumed to be the most likely natural driver of climate change.

Tying those factors together in order to estimate solar irradiance variations in the past is crucial for attributing past climate changes, particularly in the pre-industrial.

See e.g. this review paper (Schmidt et al, 2004), where the response of a climate model to estimated past changes in natural forcing due to solar irradiance variations and explosive volcanic eruptions, is shown to match the spatial pattern of reconstructed temperature changes during the «Little Ice Age» (which includes enhanced cooling in certain regions such as Europe).

They claim that the evidence for Milankovitch forcing of the ice ages implies that the planet is hypersensitive to solar irradiance variations.

Douglas Hoyt and Kenneth Schatten, «A Discussion of Plausible Solar Irradiance Variations, 1700 - 1992,» Journal of Geophysical Research, v. 98, no.

Solar forcing is the only known natural forcing acting to warm the climate over this period but it has increased much less than greenhouse gas forcing, and the observed pattern of long term tropospheric warming and stratospheric cooling is not consistent with the expected response to solar irradiance variations.

Krivova, N. A., Solanki, S. K., Fligge, A. & Unruh, Y. C. Reconstruction of solar irradiance variations in cycle 23: is solar surface magnetism the cause?

Thus, the basic magnitude of the solar irradiance variations is given by the difference between the irradiance of the present quiet Sun (composed from a distribution of brightness components defined in Appendix A) and the irradiance from component A (see Eq.

This provides strong support for the hypothesis that solar irradiance variations are caused by changes in the amount and distribution of magnetic flux at the solar surface.

The model assumes that solar irradiance variations are caused by surface magnetism and its single free parameter is kept at the same value for both cycles.

Not exact matches

11 Duration, in years, of a typical solar cycle, natural variations in the number of sunspots and flares that affect solar irradiance levels on Earth.

Solar irradiance modulation of Equator - to - Pole (Arctic) temperature gradients: Empirical evidence for climate variation on multi-decadal timescales

Dr. Benestad states: «From regression analysis cited by the authors (Douglass and Clader 2002, White et al. 1997), it seems possible that the sensitivity of global surface temperature to variations of total solar irradiance might be about 0.1 K / Wm -2.

On the other hand, Esper's data appear to be in close agreement with variations in cosmogenic isotopes whose production rates are indicators of variation in solar irradiance, and thus, global temperatures on Earth.

Typhoon variability was likely modulated further by the state of the East Asia summer monsoon (EASM) pattern, associated with variation in the magnitude of solar irradiance.

Flood layer frequency in the Ammersee sediment record depicts distinct multi-decadal variations and significant correlations to a total solar irradiance reconstruction (r = − 0.4, p < 0.0001) and 14C production rates (r = 0.37, p < 0.0001), reflecting changes in solar activity.

Contributions from the following topics (but not exclusively) are invited: • Solar irradiance and energetic particle impacts on the atmosphere • Upper atmospheric dynamical variability and coupling between atmospheric layers • Solar variations and stratosphere - troposphere coupling • Solar influence on climate variability • Solar irradiance (spectral and total irradiance) variations

Important manifestations of such external forcing from space to the atmosphere are the variations in different solar parameters such as the solar irradiance (including solar UV) and solar particle fluxes, which can induce changes in the atmosphere both at local and global scales, and can influence over a large range of altitudes.

Changes in insolation are also thought to have arisen from small variations in solar irradiance, although both timing and magnitude of past solar radiation fluctuations are highly uncertain (see Chapters 2 and 6; Lean et al., 2002; Gray et al., 2005; Foukal et al., 2006).

Jim Cross (268)-- Somewhere I came across a paper showing that variations in solar irradiance proxies, sunspots and Be10, for other than the sunspot pseudoperiodic «cycle», are best explained as random events.

We only have direct observations of total solar irradiance (TSI) since the beginning of the satellite era and substantial evidence for variations in the level of solar activity (from cosmogenic isotopes or sunspot records) in the past.

Because of the variations of sunspots and faculae on the sun's surface, the total solar irradiance (TSI), also called the solar constant, varies on a roughly 11 - year cycle by about 0.07 %, which has been measured by orbiting satellites since 1978 [Lean, 1987, 1991; Wilson et al., 1981].

...» We describe the variations with time of the solar irradiance and of the flux of ejected magnetised plasma.

In the May issue of Astronomy & Astrophysics, Shapiro et al. present a new long - term reconstruction of the solar irradiance that implies much greater variation over the last 7000 years than any previous ly reconstruction.

Recent sun - cloud connections have a decreasing correlation with CRF, but a good correlation between (low) clouds and solar irradiance, see figure 1 in http://folk.uio.no/jegill/papers/2002GL015646.pdf Also in the 6 May 2005 Science, there is an article which finds a long - term link between solar intensity (based on 14C variations) and monsoon intensity over the past 9000 years...

The Top Of Atmosphere solar irradiance varies from about 1365.4 watts per meter squared to about 1366.4 watts / M ^ 2, but that variation (less than 1 %) doesn't modulate the global temperature significantly — see http://www.woodfortrees.org/plot/pmod/from:1978/mean:10/offset:-1366/plot/wti/from:1978/mean:10

[Response: In the 19 models studied in Santer et al (2005)(Table 1), 11 models have historical variations in solar irradiance, 7 don't, and one was uncertain.

Or, even more broadly, we know there's approx. 0,1 % variation of solar irradiance between two cycles minima (Willson 2003), how do we exclude with reasonable confidence the hypothesis that there is a 1 % variation between 21.000 y BP and 1750 AD?

The IPCC 2001 report states «Several recent reconstructions estimate that variations in solar irradiance give rise to a forcing at the Earth's surface of about 0.6 to 0.7 Wm - 2 since the Maunder Minimum and about half this over the 20th century... All reconstructions indicate that the direct effect of variations in solar forcing over the 20th century was about 20 to 25 % of the change in forcing due to increases in the well - mixed greenhouse gases.»

Title: «Shortwave forcing of the Earth's climate: Modern and historical variations in the Sun's irradiance and Earth's reflectance» Author, P.R. Goode, E. Pallé Journal: Journal of ATMOSPHERIC and SOLAR - TERRESTRIAL PHYSICS DoP: Sept 2007 DOI: 10.1016 / j.jastp.2007.06.011

The clear seasonal pattern in generation rates reflects variation in solar irradiance, which is higher in the summer and lower in the winter.

Increasing CO2 does increase the greenhouse effect, but there are other factors which determine climate, including solar irradiance, volcanism, albedo, orbital variations, continental drift, mountain building, variations in sea currents, changes in greenhouse gases, even cometary impacts.

When reconstructing Earth's climate history, it can't be explained without including all the various influences, including solar irradiance, volcanism, albedo, orbital variations, continental drift, mountain building, variations in sea currents, changes in greenhouse gases, even cometary impacts.

CO2 concentrations are meaningless — it's water in all it's phases reacting to variations in solar irradiance brought on by various solar cycles and orbital cycles that controls climate — PERIOD!

However, it is not the variation in the TSI (total solar irradiance) which is causing the change.

The Holy Grail of climatology has always been to ascertain whether, and if so how, the sun might affect the Earth's energy budget to cause the climate swings observed throughout history despite the apparent inadequacy of the tiny variations in Total Solar Irradiance (TSI) that occur from one series of solar cycles to anoSolar Irradiance (TSI) that occur from one series of solar cycles to anosolar cycles to another.

These warming trends are consistent with the response to increasing greenhouse gases and sulphate aerosols and likely can not be explained by natural internal climate variations or the response to changes in natural external forcing (solar irradiance and volcanoes).

Oceanic oscillations are sufficient to cancel out or enhance the effects of natural variations in solar irradiance or other forms of solar input to the heat budget of the Earth for variable periods of time.

«Holocene Climatic Change, 14c Wiggles and Variations in Solar Irradiance.»

The solar effect on climate has been discounted by the climate modellers because the variation in total solar irradiance...

The solar constant varies, but by the same % irradiance variation for each freq band.

The NCEP model is forced by spectral irradiances but, if i understood correctly, the solar cycle variation refers to total solar irradiance only.

Whatever wide - ranging coherence one finds at multi-decadal frequencies is more likely the result of global - scale variations in cloud - regulated thermalization of solar irradiance and the lagged advection of heat from the tropics by winds and ocean currents.

A third example would be the research on how incoming solar irradiance influences China's thermometer temperature records, showing that over periods of many decades the variations in total solar irradiance in the upper atmosphere are matched by variations at the surface.