Sentences with phrase «know volcanic aerosols»

Not exact matches

Besides knowing a lot more about the transport of volcanic aerosols in the atmosphere, modern researchers had communications lines and satellites so that news of an eruption could be relayed quickly and the effects noted as they unfolded.

Researchers know that large amounts of aerosols can significantly cool the planet; the effect has been observed after large volcanic eruptions.

Knowing both the physical location and the altitude distribution of aerosols in the volcanic cloud allow more accurate forecasts in the days, weeks and months after an eruption.

Scientists have long known of the cooling effect of major volcanic eruptions, which spew large amounts of light - scattering aerosols into the stratosphere.

The effects of aerosol injections are at least somewhat known, since volcanic eruptions produce aerosols naturally and have produced cooling in the past.

Does this not show that the models that incorporate volcanic forcing can not model aerosol forcing since there are no measurements to use to parameterize and per Hansen, we do not know enough to use first principles.

There is no right answer for this, since we lack any basis to forecast whether a volcanic eruption will happen and what it's contribution to stratospheric aerosols will be.

Some of these forcings are well known and understood (such as the well - mixed greenhouse gases, or recent volcanic effects), while others have an uncertain magnitude (solar), and / or uncertain distributions in space and time (aerosols, tropospheric ozone etc.), or uncertain physics (land use change, aerosol indirect effects etc.).

The short - term cooling imparted by volcanic aerosols is clearly non-anthropogenic, but these forcings are reasonably well known from relevant observational data.

This reveals an ignorance of the literature, otherwise you'd know that the extent of aerosol cooling is estimated from the measured aerosol optical depth due to volcanic eruptions and their consequent impact on global temperature, and estimates of aerosol emissions during the 20th century.

Since the last ~ 17 years is the only period with known low volcanic forcing and since aerosol forcing is one of the largest unknowns, that makes the last 17 years the longest useful period of that type.

Taking out ENSO from a climate regression is different from taking out volcanic aerosols, because we don't know if ENSO is itself a forcing, an endogenous response to forcings, a temporally varying exogenous shift in the response of the climate to forcings, or what.

As far as the original post goes, if you simply look at calculated forcings from known sources (Volcanic Aerosol, Solar Irradience and Greenhouse gases) you can replicate the last 150 years of temperature records surprisingly well; take any of these factors out and you can not.

Regarding your statement, «Perhaps it is known that the natural variations in surface temperature are all due to unforced mechanisms, otherwise it is simply an assertion», I assume by «natural variations» you mean ENSO, PDO, AMO, etc., because obviously natural changes in solar irradiance or volcanic aerosols are recognized as forcing mechanisms.

Li et al., 2017 (DOI: 10.1016 / j.quascirev.2017.01.009): «Additionally, increased El Nino - Southern Oscillation (ENSO) strength (possibly El Ni ~ no - like phases) during drying periods, increased volcanic eruptions and the resulting aerosol load during cooling periods, as well as high volumes of greenhouse gases such as CO2 and CH4 during the recent warming periods, may also play a role in partly affecting the climatic variability in NC, superimposing on the overall solar dominated long - term control.»

The technique, which is known as «stratospheric aerosol injection», could cool the planet in a similar way to a large volcanic eruption.

I'd be curious if anyone knows how much they thought about the question of volcanic («natural») vs anthropic aerosols.

Sadly, I don't know much about this debate over the duration of volcanic aerosol effects.

Large volcanic eruptions eject sulfur dioxide, which rapidly forms tiny particles in the air known as «aerosols» that block sunlight.

We know that aerosols trump CO2 both through logic and through the empirical evidence associated with volcanic eruptions.

Radiative forcing time series for the natural forcings (solar, volcanic aerosol) are reasonably well known for the past 25 years (although these forcings continue to be debated), with estimates further back in time having increasingly large uncertainties.

«When the data are adjusted to remove the estimated impact of known factors on short - term temperature variations (El Nino / southern oscillation, volcanic aerosols and solar variability), the global warming signal becomes even more evident as noise is reduced.»

What does seem to be known is that aerosols fall out of the lower atmosphere (as high as they can be launched with conventional bombs) in days, and persist for less than 2 years when launched into the stratosphere by a major volcanic event like Pinatubo which was equivalent to several H bombs.

In the climate case, we need to know how well we estimated forcings (greenhouse gases, volcanic effects, aerosols, solar etc.) in the projections.

The total forcing Q is known through observation to take large drops after volcanic eruptions (from the volcanic aerosols reflecting away the sunlight), with similarly large and fast recoveries.