Sentences with phrase «solar changes to account»

Not exact matches

Satellite measurements and a model of how efficiently maize converts that light to mass, reveal that solar brightening, an increase in the sunlight penetrating the atmosphere and reaching Earth, accounted for 27 % of the yield increase U.S. Corn Belt farmers have observed between 1984 and 2013, researchers report today in Nature Climate Change.

I say «may» because research that tries to take gaps in measurement into account (particularly in the fast warming Arctic) or that takes into account temporary phenonomena (like volcanoes, solar variability, etc) show that there has barely been any slowdown in this one aspect of climate change.

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.

Thus it appears that, provided further satellite cloud data confirms the cosmic ray flux low cloud seeding hypothesis, and no other factors were involved over the past 150 years (e.g., variability of other cloud layers) then there is a potential for solar activity induced changes in cloudiness and irradiance to account for a significant part of the global warming experienced during the 20th century, with the possible exception of the last two decades.

In my opinion, climate behaves in a far from linear way, with loads of factors to take into account, so in most cases it would be very difficult to find climate records react consistently (over several solar cycles / decades / centuries) in the same way to say a solar change (see the Hoyt & Schatten 1998 book).

First, for changing just CO2 forcing (or CH4, etc, or for a non-GHE forcing, such as a change in incident solar radiation, volcanic aerosols, etc.), there will be other GHE radiative «forcings» (feedbacks, though in the context of measuring their radiative effect, they can be described as having radiative forcings of x W / m2 per change in surface T), such as water vapor feedback, LW cloud feedback, and also, because GHE depends on the vertical temperature distribution, the lapse rate feedback (this generally refers to the tropospheric lapse rate, though changes in the position of the tropopause and changes in the stratospheric temperature could also be considered lapse - rate feedbacks for forcing at TOA; forcing at the tropopause with stratospheric adjustment takes some of that into account; sensitivity to forcing at the tropopause with stratospheric adjustment will generally be different from sensitivity to forcing without stratospheric adjustment and both will generally be different from forcing at TOA before stratospheric adjustment; forcing at TOA after stratospehric adjustment is identical to forcing at the tropopause after stratospheric adjustment).

Also, if one uses a simple grey earth model one finds that not taking into account the distribution of radiative forcing of changes in solar irradiance overestimates its strength by a factor of 2 - 3 compared to greenhouse gas forcing.

; what leads you to believe that the physical and biological trends we've seen / measured are likely to reverse within a mere 20 years, especially if / as we enter a solar upswing; how have you accounted for warming - driven methane release; what credible peer reviewed literature on «the other side» are you describing; what supports your confidence that there is little to no probability that the AGW that you do accept will change weather patterns enough to disrupt crop planting / growing / harvesting / production severely (or do you classify famine as a natural phenomenon?)?

But climate models of global warming should be corrected to better account for changes in solar activity, according to Nicola Scafetta and Bruce West of Duke University.

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.

I have sought the best empirical evidence to show how changes in incoming solar radiation, accounted for by intrinsic solar magnetic modulation of the irradiance output as well as planetary modulation of the seasonal distribution of sunlight, affects the thermal properties of land and sea, including temperatures.

«The results also show that ionisation of the atmosphere by cosmic rays accounts for nearly one - third of all particles formed, although small changes in cosmic rays over the solar cycle do not affect aerosols enough to influence today's polluted climate significantly.»

---- Now you realize that astronomical forcing (so - called Milankovitch) does not provide enough change in solar insolation in and of itself to account for the full temperature swings we see from the bottom of the glacial to the top of the interglacial.

The results indicate a primary role of solar motion in a causal chain of ST - relations and a need of taking the Solar System as a whole into account to explain climatic chasolar motion in a causal chain of ST - relations and a need of taking the Solar System as a whole into account to explain climatic chaSolar System as a whole into account to explain climatic changes.

Using conventional energy accounting, a switch from coal & gas generation to solar / wind would reduce our primary energy consumption by 2/3, and yet the electricity generated wouldn't change at all.

The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an (unknown) amplifying mechanism.

Consider this key sentence: «The (climate) forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an amplifying mechanism such as the hypothesized GCR - cloud link.»

In order to determine the solar contribution, we have to start with the solar radiative forcing, which is the change in total solar irradiance (TSI) in Watts per square meter (W / m2) divided by 4 to account for spherical geometry, and multiplied by 0.7 to account for planetary albedo (Meehl 2002).

Thus, long - term variations of TSI (with account for their direct and secondary, based on feedback effects, influence) are the main fundamental cause of climate changes since variations of the Earth climate is mainly determined by a long - term imbalance between the energy of solar radiation entering the upper layers of the Earth's atmosphere and the total energy emitted from the Earth back to space.»

The temporal lag is needed to account for the large mass of Neptune that would require years to adjust to any changes in solar output.

Essentially, every timestep the model calculates the forcing from CO2 and reduces incoming solar radiation to offset that, taking changing planetary albedo into account.

As regards AGW I am already convinced that Bob's work has helped to do the business of scotching that by helping to point out that most if not all of the 20th century temperature changes can be accounted for by oceanic and solar behaviour without invoking CO2.

The most likely candidate for that climatic variable force that comes to mind is solar variability (because I can think of no other force that can change or reverse in a different trend often enough, and quick enough to account for the historical climatic record) and the primary and secondary effects associated with this solar variability which I feel are a significant player in glacial / inter-glacial cycles, counter climatic trends when taken into consideration with these factors which are, land / ocean arrangements, mean land elevation, mean magnetic field strength of the earth (magnetic excursions), the mean state of the climate (average global temperature), the initial state of the earth's climate (how close to interglacial - glacial threshold condition it is) the state of random terrestrial (violent volcanic eruption, or a random atmospheric circulation / oceanic pattern that feeds upon itself possibly) / extra terrestrial events (super-nova in vicinity of earth or a random impact) along with Milankovitch Cycles.

The NSRDB accounts for any recent climate changes and provides more accurate values of solar radiation due to a better model for estimating values (more than 90 percent of the solar radiation data in both data bases are modeled), more measured data including direct normal radiation, improved instrument calibration methods, and rigorous procedures for assessing quality of data.

To account for these changing needs, utilities are increasingly incorporating rooftop solar into their planning practices.

«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.

dw = 0.05; % change in wavelength for each step — need to ensure «integrals» work ww = (0.1:0.05:4)»; % wavelengths to evaluate alb = 0.3; costheta = 1; % take into account reflection of solar, and later, angle from zenith rs = planckm (ww, 5780)».

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.

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.

Assuming a CR - cloud connection exists, there are various factors which could potentially account for a lack of detection of this relationship over both long and short timescales studies, including: uncertainties, artefacts and measurement limitations of the datasets; high noise levels in the data relative to the (likely low) amplitude of any solar - induced changes; the inability of studies to effectively isolate solar parameters; or the inability to isolate solar - induced changes from natural climate oscillations and periodicities.

«Third, in a period when ocean basins were similar to modern, ice age climate sensitivity to pCO2 changes is underestimated by climate models even when long term changes in solar forcing and ice sheet size and distribution are taken into account, implying that internal positive feedbacks are stronger than previously thought.»

st Order Draft, the Second Order Draft, p7, cites several papers re empirical relationships between GCR and aspects of the climate system and notes: «The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an amplifying mechanism such as the hypothesiz GCR - cloud link.»

The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of this unknown amplifying mechanism.The cosmic ray - ionization mechanism is too weak to influence global concentrations of CCN or their change over the last century or during a solar cycle in any climatically significant way.

The forcingfrom changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an (unknown) amplifying mechanism.

Source energy: (1) Change from per square foot basis to per person; (2) Change the source energy factor to the US average of 3.16; (3) Base the lighting and miscellaneous electrical loads on American numbers (from RESNET); (4) «Set the source energy limit to 6,200 kWh / person / year and tighten it to 4,200 kWh / person / year within a few years;» and (5) Account for photovoltaic (PV) inputs or other on - site renewable electricity the same way solar hot water is.

In the thermosphere, there are relatively few (compared to the troposphere) other sources of climate change; our results largely account for the effects of the major source, solar EUV radiation.

Since solar effects, both direct and indirect, are more than sufficient to account for net estimated temperature change over the period of significant fossil fuel usage, have humans been warming or cooling the planet?

In my articles to date I have been unwilling to claim anything as grand as the creation of a new model of climate because until now I was unable to propose any solar mechanism that could result directly in global albedo changes without some other forcing agent or that could account for a direct solar cause of discontinuities in the temperature profile along the horizontal line of the oceanic thermohaline circulation.

Regional climatic changes played a role as well, which was particularly relevant in Amazon rainforests, which accounted for 42 % of the global NPP increase, owing mainly to decreased cloud cover and the resulting increase in solar radiation (note that it is basically impossible to determine how much of this increase in NPP is a result of recent global climate change vs. natural climate variability, although both are likely to have played a role).

Another account covers the U.K.'s cuts to solar subsidies, saying: «The government says the changes were necessary to protect bill payers, as the solar incentives are levied on household energy bills.»

With regard to proxy studies, same basic questions, are these direct or passive correlations, what evidence that tree ring core thickness depends only on temperature (what about precipitation, cloud cover, volcanic activity, sea surface temperatue changes, sea current changes, solar irradiance changes, cloud cover, etc.) How are these variables accounted for when analysis of ice cores is completed, or for that matter when computer models, and / or proxy studies are completed.

The models heavily relied upon by the Intergovernmental Panel on Climate Change (IPCC) had not projected this multidecadal stasis in «global warming»; nor (until trained ex post facto) the fall in TS from 1940 - 1975; nor 50 years» cooling in Antarctica (Doran et al., 2002) and the Arctic (Soon, 2005); nor the absence of ocean warming since 2003 (Lyman et al., 2006; Gouretski & Koltermann, 2007); nor the onset, duration, or intensity of the Madden - Julian intraseasonal oscillation, the Quasi-Biennial Oscillation in the tropical stratosphere, El Nino / La Nina oscillations, the Atlantic Multidecadal Oscillation, or the Pacific Decadal Oscillation that has recently transited from its warming to its cooling phase (oceanic oscillations which, on their own, may account for all of the observed warmings and coolings over the past half - century: Tsoniset al., 2007); nor the magnitude nor duration of multi-century events such as the Mediaeval Warm Period or the Little Ice Age; nor the cessation since 2000 of the previously - observed growth in atmospheric methane concentration (IPCC, 2007); nor the active 2004 hurricane season; nor the inactive subsequent seasons; nor the UK flooding of 2007 (the Met Office had forecast a summer of prolonged droughts only six weeks previously); nor the solar Grand Maximum of the past 70 years, during which the Sun was more active, for longer, than at almost any similar period in the past 11,400 years (Hathaway, 2004; Solankiet al., 2005); nor the consequent surface «global warming» on Mars, Jupiter, Neptune's largest moon, and even distant Pluto; nor the eerily - continuing 2006 solar minimum; nor the consequent, precipitate decline of ~ 0.8 °C in TS from January 2007 to May 2008 that has canceled out almost all of the observed warming of the 20th century.

DePreSys (18) takes into account the observed state of the atmosphere and ocean in order to predict internal variability, together with plausible changes in anthropogenic sources of greenhouse gases and aerosol concentrations (19) and projected changes in solar irradiance and volcanic aerosol (20).