Sentences with phrase «from solar variation»

In fact, the forcing from solar variation is not particularly large.

A variety of natural factors influence global climate, from solar variation to volcanoes, but anthropogenic greenhouse gas emissions also change the nature of the planet.

Not exact matches

Trenberth points to disconcerting discrepancies and spurious variations in records, including those of precipitation and solar radiation, derived from different satellite sensors.

2015 is slightly above the red line because of a small push from El Niño as well as even smaller contributions from solar radiation and random weather variations.

During solar flares, variation in the solar flux in the spectral range extending from the UV to the X-ray wavelengths can have a direct effect on the ionization of the atmospheres of planetary bodies as well as on their heating and dimensions (for details see Schunk & Nagy 2009).

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.

Their analysis resulted in AGHG «forcing» effects on global temperatures 10 times that from variations in the sun's solar activity.

The mean insolation at Earth orbit is about 1366 W / m ^ 2; the peak - to - peak variation over the 11 year solar cycle is about 3 W / m ^ 2; the authors discuss two running averages derived from different satellite data sets and analysis derived by Willson and Mordvinov (2003) and Frohlich and Lean (1998) respectively.

Periods of volcanism can cool the climate (as with the 1991 Pinatubo eruption), methane emissions from increased biological activity can warm the climate, and slight changes in solar output and orbital variations can all have climate effects which are much shorter in duration than the ice age cycles, ranging from less than a decade to a thousand years in duration (the Younger Dryas).

Conclusion: The analysis of the relationship between variations in solar activity and SST from 1901 to 2011 indicated that sunspot numbers and SST were positively correlated in wide areas, with statistically significant positive correlations in many regions.

Further in their Fig. 1 Courtillot et al. show geochemical data from a Central Alpine stalagmite which purports to establish a highly tight correlation between climate variations and a solar activity proxy; as Bard and Delaygue note, Courtillot and co-workers have concealed the fact that the correlation is so good precisely because the chronology of the two series being compared has been finely tuned to expressly maximize the correlation.

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

In fact, scientists have long recognized the importance of solar variability as one of the factors governing climate (see the very scholarly review of the subject by Bard and Frank, available here at EPSL or here as pdf) An understanding of solar variability needs to be (and is) taken into account in attribution of climate change of the past century, and in attempts to estimate climate sensitivity from recent climate variations.

As a result, temperature variations on Mercury are the most extreme in the Solar System ranging from -183 °C -LRB--298 °F) to 427 °C (800 °F), although its average surface temperature is 167 °C (333 °F).

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.

These orbital variations, which can be calculated from astronomical laws (Berger, 1978), force climate variations by changing the seasonal and latitudinal distribution of solar radiation (Chapter 6).

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).

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.

It is to be noted here that there is no necessary contradiction between forecast expectations of (a) some renewed (or continuation of) slight cooling of world climate for a few decades to come, e.g., from volcanic or solar activity variations; (b) an abrupt warming due to the effect of increasing carbon dioxide, lasting some centuries until fossil fuels are exhausted and a while thereafter; and this followed in turn by (c) a glaciation lasting (like the previous ones) for many thousands of years.»

Mike's work, like that of previous award winners, is diverse, and includes pioneering and highly cited work in time series analysis (an elegant use of Thomson's multitaper spectral analysis approach to detect spatiotemporal oscillations in the climate record and methods for smoothing temporal data), decadal climate variability (the term «Atlantic Multidecadal Oscillation» or «AMO» was coined by Mike in an interview with Science's Richard Kerr about a paper he had published with Tom Delworth of GFDL showing evidence in both climate model simulations and observational data for a 50 - 70 year oscillation in the climate system; significantly Mike also published work with Kerry Emanuel in 2006 showing that the AMO concept has been overstated as regards its role in 20th century tropical Atlantic SST changes, a finding recently reaffirmed by a study published in Nature), in showing how changes in radiative forcing from volcanoes can affect ENSO, in examining the role of solar variations in explaining the pattern of the Medieval Climate Anomaly and Little Ice Age, the relationship between the climate changes of past centuries and phenomena such as Atlantic tropical cyclones and global sea level, and even a bit of work in atmospheric chemistry (an analysis of beryllium - 7 measurements).

If there was more natural variation in the past millenia, specifically due to solar changes, then that goes at the cost of the GHG / aerosol combination, as both are near impossible to distinguish from each other in the warming of the last halve century... Solar activity has never been as high, and for an as long period, as current in the past millenium (and even the past 8,000 yesolar changes, then that goes at the cost of the GHG / aerosol combination, as both are near impossible to distinguish from each other in the warming of the last halve century... Solar activity has never been as high, and for an as long period, as current in the past millenium (and even the past 8,000 yeSolar activity has never been as high, and for an as long period, as current in the past millenium (and even the past 8,000 years).

The solar cycle is visible in the upper 150 m of the oceans, with a variation in SST of ~ 0.1 K, from a TOA solar change of 0.5 - 1.5 W / m2.

The mean insolation at Earth orbit is about 1366 W / m ^ 2; the peak - to - peak variation over the 11 year solar cycle is about 3 W / m ^ 2; the authors discuss two running averages derived from different satellite data sets and analysis derived by Willson and Mordvinov (2003) and Frohlich and Lean (1998) respectively.

Thus, solar cycle variations may or may not explain this «dip» (one similar - looking dip in two curves is not a significant correlation and could easily be coincidence; there is a better - founded explanation for this «dip» resulting from cooling by aerosol emissions — see the figure from Hansen et al. coming up below).

The increase / decrease of net upward LW flux going from one level to a higher level equals the net cooling / heating of that layer by LW radiation — in equilibrium this must be balanaced by solar heating / cooling + convective / conductive heating / cooling, and those are related to flux variation in height in the same way.

If one takes the Moberg reconstruction as base, the variation was ~ 0.8 K, again of which less than 0.1 K from volcanic, thus 0.7 K from solar changes.

Recently I have been looking at the climate models collected in the CMIP3 archive which have been analysed and assessed in IPCC and it is very interesting to see how the forced changes — i.e. the changes driven the external factors such as greenhouse gases, tropospheric aerosols, solar forcing and stratospheric volcanic aerosols drive the forced response in the models (which you can see by averaging out several simulations of the same model with the same forcing)-- differ from the internal variability, such as associated with variations of the North Atlantic and the ENSO etc, which you can see by looking at individual realisations of a particular model and how it differs from the ensemble mean.

Here again I completely part with solar proponents, there are so many instruments about measuring the sun everywhere, from space, from the ocean, even underground (cosmic rays), there are none as it is often repeated, no solar variation to justify GW present conditions.

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

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

If one takes the MBH98 / 99 reconstruction as base, the variation in the pre-industrial period was ~ 0.2 K, of which less than 0.1 K (in average) from volcanic eruptions, the rest mostly from solar (I doubt that land use changes had much influence on global temperatures).

# 57 Solar activity (if you mean TSI) has no clear trend from 1980s (if any, less pronounced than the difference bewteen a minimum and a maximum in a cycle, and I'm not informed of a statistical link between solar cycle variation and cyclone activSolar activity (if you mean TSI) has no clear trend from 1980s (if any, less pronounced than the difference bewteen a minimum and a maximum in a cycle, and I'm not informed of a statistical link between solar cycle variation and cyclone activsolar cycle variation and cyclone activity).

About the comments from Urs, The climate sensitivity to solar variations can not be 1/2 (as Urs claims) or 2 times (as Rasmus claims) larger that what I estimated for the simply reason that there would be no match between the data patterns.

Royer 2006 combined the radiative forcing from CO2 and solar variations to find their net effect on climate.

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.

It is currently on average around 0.2 C / decade [Note the IPCC claimed 0.34 C], actually smaller than the annual noise from natural annual variation of the temperature due to ocean currents and volcanoes and in the range of solar activity fluctuations.»

If we scale sunspot numbers so that the variations from solar minimum to maximum represent about a 0.1 deg change in temperature, and if we lag the sunspot data 6 years, it compares well visually with the adjusted GISS LOTI data.

The global temperature switches from cooling to warming mode frequently as a result of the ever changing interplay between variations in solar influence and intermittent heat flows from the oceans.

And because cloud cover gates the Sun on and off, it is the most powerful feedback in all of Earth's climate to amplify solar variations and to mitigate global warming from any cause.

For an even more detailed understanding of solar activity and Earth's climate, read a paper from the Danish Meteorological Institute, in Copenhagen (K. Lassen, Long - term Variations in Solar Activity..., http://www.tmgnow.com/repository/solar/lassen1.hsolar activity and Earth's climate, read a paper from the Danish Meteorological Institute, in Copenhagen (K. Lassen, Long - term Variations in Solar Activity..., http://www.tmgnow.com/repository/solar/lassen1.hSolar Activity..., http://www.tmgnow.com/repository/solar/lassen1.hsolar/lassen1.html).

Major ice ages came and went from natural causes, mainly variations in Earth's orbit and the incoming solar energy, especially nearer the poles.

But if they can be linked to warmer conditions globally, then these would be most likely caused by solar variations or cosmic rays, a recovery from the LIA and certainly not due to increases in CO2 levels, which aren't caused by human emissions anyway.

Presumably this yearly variation is related to the variation in solar energy input to the earth, which is maximum in January when the earth is closest to the sun and minimum in July when the earth is at maximum distance from the sun.

The «new» solar TSI estimate is 1360.8Wm - 2, the annual variation is from around 1321 to 1413 Wm - 2.

My understanding from Leif is that solar variation over the last century or more has been overstated.

Variations in climate parameters at time intervals from hundreds to tens of millions of years in the past and its relation to solar activity; Raspopov et al, 2010, see abstract here.

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.

Another major climate oscillation around 7500 — 7000 cal BP may have resulted from combined effects of a strong rate of change in insolation and of variations in solar activity.»

Instead they offer a theory that climate change probably derives predominantly from natural ocean - atmosphere oscillations and / or by natural solar variations (irradiation and cosmic ray flux) and / or by natural cloud cover variations and / or the Milankovitch Effect, i.e. it is probably predominantly just natural.

Story submitted by Cornelis de Jager (past president ICSU; past pres. COSPAR) In a recent publication entitled Terrestrial ground temperature variation in relation to solar magnetic variability, including the present Schwabe cycle, Cornelis (Kees) de Jager and Hans Nieuwenhuijzen, from the Space Research Organisation of the Netherlands have analysed the dependence of the global earth temperature...