Sentences with phrase «stratospheric o3»

An important issue is whether the actual surface temperature responses to the forcing by stratospheric O3 has the same relationship with forcing as obtained for, say, CO2 or solar constant changes.

This is further substantiated by Christiansen (1999) who shows that the higher climate sensitivity for upper stratospheric O3 losses relative to lower stratospheric depletion is related to the vertical partitioning of the forcing, in particular the relative roles of short - wave and long - wave radiation in the surface - troposphere system.

Compared to, say, CO2 change, the stratospheric O3 forcing is not global in extent, being very small in the tropics and increasing from mid - to high latitudes; the O3 forcing also differs in its vertical structure, since the radiative forcings for CO2 change in both the troposphere and surface are of the same sign (WMO, 1986).

The evolution of the forcing due to stratospheric O3 loss hinges on the rate of recovery of the ozone layer, with special regards to the spatial structure of such a recovery in the mid - to high latitudes.

The forcing by lower stratospheric O3 is an unusual one in that it has a positive short - wave and a negative long - wave radiative forcing.

It is encouraging that the global mean climate sensitivity parameter for cases involving lower stratospheric O3 changes and that for CO2 changes (viz., doubling) are reasonably similar in Christiansen (1999) while being within about 25 % of a central value in Hansen et al. (1997a).

Solomon and Daniel (1996) point out that the global mean stratospheric O3 forcing can be expected to scale down substantially in importance relative to the well - mixed greenhouse gases, in view of the former s decline and the latter s sustained increase in concentrations.

In arriving at a best estimate for the forcing, we rely essentially on the studies that have made use of stratospheric O3 observations directly.

Note, however, that the evolution of the negativity of the stratospheric O3 forcing may vary considerably with latitude and season i.e., the recovery may not occur at all locations and seasons at the same rate.

Another feedback has been identified for the addition of N2O to the atmosphere; it is associated with stratospheric O3 chemistry and shortens the perturbation lifetime relative to the global atmospheric lifetime of N2O by about 5 %.

Randall et al. [1998, 2001] presented evidence from the Polar Ozone and Aerosol Measurement (POAM) II and III instruments for stratospheric O3 reductions caused by the EPP IE, showing depletions of 40 — 45 % in middle stratospheric O3 mixing ratios.

► Impact of different factors on lower stratospheric O3 variability is estimated.

Not exact matches

But in this case, is the stratospheric trend of any help to infer a solar UV or TSI trend, if O3 and CO2 are the main drivers?

The most important of these gases is CH4, whose reduction in turn reduces tropospheric O3 and stratospheric H2O.

Interestingly, going from (among H2O, CO2, and O3) only H2O vapor to H2O + CO2, there is stratospheric warming.

Stratospheric cooling due to CO2 is predominantly in the upper stratosphere, in the lower it's due to O3.

Kiehl et al. (1999) obtained a radiative forcing of -0.187 Wm - 2 using the O3 profile data set describing changes since the late 1970s due to stratospheric depletion alone, consistent with the range of other models (see Shine et al., 1995).

It is shown that an analytical equation derived from the CRE theory reproduces well 11 - year cyclic variations of polar O3 loss and stratospheric cooling, and new statistical analyses of the CRE equation with observed data of total O3 and stratospheric temperature give high linear correlation coefficients ≥ 0.92.

Secondly, natural and anthropogenic contributions to these phenomena are examined in detail and separated well through in - depth statistical analyses of comprehensive measured datasets of quantities, including cosmic rays (CRs), total solar irradiance, sunspot number, halogenated gases (CFCs, CCl4 and HCFCs), CO2, total O3, lower stratospheric temperatures and global surface temperatures.

If that stratospheric moisture is due to CH4 reacting with O3 then the chemistry modules needs to be tweaked.