Uncertainties in emission projections of gaseous pollutants and aerosols (especially secondary organic components) need to be addressed urgently to advance our understanding of climate forcing. The role of greenhouse gases (such as water vapor, CO2, O3, and CH4) and aerosols in climate change has been highlighted as a key area of future research. In relation to aerosols, their diverse sources, complex physicochemical characteristics and large spatial gradients make their role in climate forcing particularly challenging to quantify. In addition to primary emissions, secondary particles, such as, nitrates, sulfates and organic compounds, also result from chemical reactions involving precursor gases such as SO^, DMS, NO^, volatile organic compounds, and oxidizing agents including ozone. One consequence of the diverse nature of aerosols is that they exhibit negative (e.g., sulfates) as well as positive (e.g., black carbon) radiative forcing characteristics. Although much effort has been directed toward gaseous species, considerable uncertainties remain in size-dependent aerosol compositional data, physical properties as well as processes controlling their transport and transformation, all of which affect the composition of the atmosphere. Probably one of the most important sources of uncertainty relates to the indirect effect of aerosols as they also contribute to multiphase and microphysical cloud processes, which are of considerable importance to the global radiative balance.
In addition to better parametrization of key processes, improvements are required in regional and global scale modeling. Resolution of regional climate information from atmosphere-ocean general circulation models remains a limiting factor. Vertical profiles of temperature, for example, in climate and AQMs need to be better described. Such limitations hinder the prospect ofreliably distinguishing between natural variability (e.g., due to natural forcing agents, solar irradiance, and volcanic effects) and human-induced changes caused by emissions of greenhouse gases and aerosols over multidecadal timescales. Consequently, the current predictions of the impact of air pollutants on climate, air quality, and ecosystems or of extreme events are unreliable. Therefore, it is very important for future research to address all the key areas of uncertainties so as to provide an improved modeling capability over regional and global scales and an improved integrated assessment methodology for formulating mitigation and adaptation strategies.
In this concern, one of the important tasks is to develop a modeling instrument of coupled 'Atmospheric chemistry/Aerosol' and 'Atmospheric Dynamics/Climate' models for integrated studies (see Figure 1).
Was this article helpful?
Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.