Sentences with phrase «of volcanic influence»

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.

The site where Loki is heavily influenced by volcanic activity, but actually quite low in temperature,» says Steffen Jørgensen from the University of Bergen in Norway, who was involved in taking the samples where Loki was found.

These results, which you can read all about in the journal Nature Geoscience, reveal the influence of surface processes — largely controlled by climate — on volcanic activity.

Although the rate of subduction varies little along the entire arc, there are complex changes in the geologic processes along the subduction zone that dramatically influence volcanic activity, crustal deformation, earthquake generation and occurrence all along the western edge of South America.

The volcanic activity may be influenced by the gravitational pulls of neighboring Ganymede and Europa.

In years influenced by volcanic eruptions, Nile flooding was generally diminished, leading to social stress that could trigger unrest and have other political and economic consequences,» says Joseph Manning, lead author on the paper and the William K. & Marilyn Milton Simpson Professor of History and Classics at Yale.

Their findings: natural influences such as changes in the amount of sunlight or volcanic eruptions did not explain the warming trends, but the results matched when increasing levels of greenhouse gas emissions were added to the mix.

However, these studies failed to account for the comprehensive set of geological variables that change over time, influencing the volcanic history.

Molten rock (or magma) has a strong influence on our planet and its inhabitants, causing destructive volcanic eruptions and generating some of the giant mineral deposits.

But despite that steady climb, not every year is warmer than the one before it, thanks to the vagaries of weather, the influence of natural climate cycles, and the effects of events like volcanic eruptions.

A new study has found geochemical clues near the summit of volcanic Mauna Kea that tell a story of ancient glacier formation, the influence of the most recent ice age, more frequent major storms in Hawaii, and the impact of a distant climatic event that changed much of the world.

2000, except that they used a large forcing for solar (10x) and volcanic (5x) in separate runs to see if the relative influence of both may need to be adjusted, as the Hadcm3 model possibly underestimates the — relative — weaker forcings.

For volcanic, there may be some overestimating of historical influences, as the influence of temperature and reduced solar input (less insolation) on tree rings is hardly to separate.

It is also well known that volcanic activity has a cooling influence, and as is well documented by the effects of the 1991 Mount Pinatubo volcanic eruption.

By comparing volcanic activity to records of social unrest, the researchers found a correlation between the two that was too closely matched to dismiss: «In years influenced by volcanic eruptions, Nile flooding was generally diminished, leading to social stress that could trigger unrest and have other political and economic consequences,» Manning said.

Over the last 30 years of direct satellite observation of the Earth's climate, many natural influences including orbital variations, solar and volcanic activity, and oceanic conditions like El Nino (ENSO) and the Pacific Decadal Oscillation (PDO) have either had no effect or promoted cooling conditions.

Additional eruptions added from tree ring data reported in Table 2 of Briffa, KR, PD Jones, FH Schweingruber & TJ Osborn, 1998, Influence of volcanic eruptions on Northern hemisphere summer temperature over the past 600 years: Nature 393, 450 - 455.

Volcanoes can — and do — influence the global climate over time periods of a few years but this is achieved through the injection of sulfate aerosols into the high reaches of the atmosphere during the very large volcanic eruptions that occur sporadically each century.

The uncertainty in the overall amplitude of the reconstruction of volcanic forcing is also important for quantifying the influence of volcanism on temperature reconstructions over longer periods, but is difficult to quantify and may be a substantial fraction of the best estimate (e.g., Hegerl et al., 2006a).

This interactive engaging NGSS STEM unit covers NGSS Standards: 5 - ESS2 - 1 Develop a model that demonstrates how the environment, earthquakes, volcanic action and glaciers influenced the formation of Yosemite Valley.

Additional eruptions added from tree ring data reported in Table 2 of Briffa, KR, PD Jones, FH Schweingruber & TJ Osborn, 1998, Influence of volcanic eruptions on Northern hemisphere summer temperature over the past 600 years: Nature 393, 450 - 455.

And relative to 2008 - 18, the extra 0.1 ppm / yr in the previous decades would be more than cloaked by volcanic influences of the 1980s & 90s.

But, as Todd in # 23 points out, 1984 could have been affected by the El Chichon eruption which means that the early part of the 1984 - 2008 period was affected by 2 volcanic eruptions which must influence the trend.

by removing the influence of exogenous factors like el Nino, volcanic eruptions, and solar variation (or at least, approximations of their influence) we can reduce the noise level in temperature time series (and reduce the level of autocorrelation in the process).

The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and human - induced forcings such as the changing composition of the atmosphere and land - use change.»

Any change in the strength of natural (volcanic, solar) influences based on historical variations will have an opposite effect on the influence of greenhouse gases, and thus on man - made emissions.

For volcanic, there may be some overestimating of historical influences, as the influence of temperature and reduced solar input (less insolation) on tree rings is hardly to separate.

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-!)

2000, except that they used a large forcing for solar (10x) and volcanic (5x) in separate runs to see if the relative influence of both may need to be adjusted, as the Hadcm3 model possibly underestimates the — relative — weaker forcings.

A fingerprinting study of the ocean data, compared to GHG / aerosols, ice volumes, solar variance and volcanic influences may give some more insight...

The decay times of volcanic aerosols are approximately exponential, though there are seasonal and geographic influences *; Observations vary from ~ 5 to 95 months for 1 / e; eruption durations vary from week to decades; the mean time between VEI 4 eruptions is 18 months.

In (b) the individual contributions of these influences are shown, namely ENSO (purple), volcanic aerosols (blue), solar irradiance (green) and anthropogenic effects (red).

But while the graph was only for SST (sea surface temperature, something different of SAT — surface air temperature, even at sea), the influence of the solar cycle and volcanic episodes (El Chicon and Pinatubo) is visible globally in the oceans until a depth of 300 m in the Levitus data.

Re # 92:... reconstructions based only on tree rings may overestimate the influence of volcanic eruptions, as not only the temperature is reduced, but there is also a change in direct and diffuse incoming sunlight...

-- But if the (negative) influence of aerosols (and volcanic) is overestimated, the modeled trend would be way too high.

Then you actually need to be able to say something about how climate change will influence El Nino, and by studying the past relationship between El Nino and natural factors like volcanic eruptions we could potentially better inform our understanding of how the El Nino phenomenon will respond to climate change.

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).

If more recent proxies are used (Esper, Moberg, bore hole reconstructions), the influence of volcanic in the total variability reduces to ~ 14 %, instead of 50 %.

For the period 1950 to 2005, it is exceptionally unlikely that the combined natural RF (solar irradiance plus volcanic aerosol) has had a warming influence comparable to that of the combined anthropogenic RF.

Bertrand was investigating the effect of solar and volcanic influence on climate and concluded «these are clearly not sufficient to explain the observed 20th century warming and more specifically the warming trend which started at the beginning of the 1970s».

You picked a time period (1980 - 1987) where the beginning was influenced by the volcanic eruption of El Chichon in 1981.

A paper published in Environmental Research Letters by Rahmstorf, Foster, and Cazenave (2012) applied the methodology of Foster and Rahmstorf (2011), using the statistical technique of multiple regression to filter out the influences of the El Niño Southern Oscillation (ENSO) and solar and volcanic activity from the global surface temperature data to evaluate the underlying long - term primarily human - caused trend.

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.

One question (not the only one but the most obvious) that comes to my mind is the influence of volcanic eruptions.

A true «prediction» can't be made because the result will depend on the future volcanic eruptions and other influences on albedo, but you can run the model for each of a couple dozen stochastic processes for the future volcanic activity.

[4] The ocean's influence extends even to the composition of volcanic rocks through seafloor metamorphism, as well as to that of volcanic gases and magmas created at subduction zones.

There they reflect sunlight back into space, mimicking the influence of large volcanic eruptions that have temporarily cooled the planet in the past.

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.

In the abstract you say that you can easily define certain effects (in the MWP period) such as GHG influence, «the reconstructions of solar, volcanic and land use - related forcing are more uncertain».

Isolation of ENSO, solar and volcanic influences the better to reveal an underlying hypothesised anthropogenic trend is disallowed?