Sentences with phrase «with volcanic influences»

But there are problems with volcanic influences.

Not exact matches

When scientists use climate models for attribution studies, they first run simulations with estimates of only «natural» climate influences over the past 100 years, such as changes in solar output and major volcanic eruptions.

As the Shindell paper shows: the influence of volcanic is within the modelled unforced variability, except for Europe, where it is outside, but with the wrong sign -LRB-!)

The most likely influence during this period is variable output from the sun combined with pronounced volcanic activity.

There we see that volcanic influence has led to cooling by up to 0.25 K and with a decay that has taken a few years.

The literature since the AR4, and the availability of more simulations of the last millennium with more complete forcing, including solar, volcanic and greenhouse gas influences, and generally also land use change and orbital forcing) and more sophisticated models, to a much larger extent coupled climate or coupled earth system models, some of them with interactive carbon cycle, strengthens these conclusions.

Compared with natural factors that influence climate (including solar variation and volcanic eruptions), human activities — primarily burning fossil fuels and deforestation — have been a major contributor to climate change over the last 50 years.

The origin of the 1400 - period begins with the 1998 paper in Nature «Influence of volcanic eruptions on northern hemisphere summer temperature over the past 600 years» As the title suggests, the paper is primarily about identifying eruptions with spikes in the record.

The Hansen paper is an extreme case, combining a strong volcanic forcing with a model with high sensitivity, and so probably provides an upper bound for the volcanic influence on temperature.

There is also another paper in discussion on the pitfalls of assuming you can remove solar / volcanic / ENSO influences with any confidence.

Moreover, the net TOA energy flux is profoundly influenced by volcanic eruptions (not new) and almost simultaneously, but with some blurring, so too is OHC.

With f anthropic (t) or f volcanic (t) or f T (t) the steady state is disturbed and that will influence both f out - gassed (t) and f absorbed (t) and thus dCO2 / dt, where the whole system tries to restore the dynamical equilibrium.

Figure 1: Global surface and lower atmosphere temperature data from 5 data sets (with a 12 - month running average) before and after applying the statistical methodology of Foster and Rahmstorf (2011) to remove the influences of ENSO and solar and volcanic activity.

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.

Argo era or 21st century is used quite a bit because it is «cleaner» less volcanic super El Nino influence and it includes more of the state of the art satellite and ocean data., you can pick any spot you like I guess for a pub conversation, but the comparison with projections is the real tell of the tape.

After accounting for seasonal bias and volcanic eruptions, Feulner finds no significant trend with the sunspot number, and that the solar activity influence is «comparatively small».

Forster et al. (2007) described four mechanisms by which volcanic forcing influences climate: RF due to aerosol — radiation interaction; differential (vertical or horizontal) heating, producing gradients and changes in circulation; interactions with other modes of circulation, such as El Niño - Southern Oscillation (ENSO); and ozone depletion with its effects on stratospheric heating, which depends on anthropogenic chlorine (stratospheric ozone would increase with a volcanic eruption under low - chlorine conditions).

Hansen et al. (1981), «emerge» p. 957; another scientist who compared temperature trends with a combination of CO2, emissions from volcanic eruptions, and supposed solar cycles, likewise got a good match, and used the cycles to predict that greenhouse warming would swamp other influences after about 2000.

From solar min to solar max the influence on temp has been estimated at around 0.1 deg C (some scientists came to 0.2), and the LIA was at least partly influenced by a sustained period of low solar activity, combined with high volcanic activity (see eg the wikipedia link I provided in the blog post).