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drivers of climate change that are significantly influenced by human activities. The overall radiative forcing of anthropogenic aerosols is negative and can offset a large portion of the global warming caused by greenhouse gases. The effects of anthropogenic aerosols on regional climate, especially over monsoon regions, have been investigated in many studies. For example, it was found that anthropogenic aerosols could weaken the East Asian summer monsoon ( Zhang et al. 2012 ) and the South Asian
drivers of climate change that are significantly influenced by human activities. The overall radiative forcing of anthropogenic aerosols is negative and can offset a large portion of the global warming caused by greenhouse gases. The effects of anthropogenic aerosols on regional climate, especially over monsoon regions, have been investigated in many studies. For example, it was found that anthropogenic aerosols could weaken the East Asian summer monsoon ( Zhang et al. 2012 ) and the South Asian
1. Introduction Field observations in recent decades have revealed an abundance of anthropogenic aerosols, particularly absorbing aerosols, over South Asia and its surrounding ocean during the dry season ( Ramanathan et al. 2001 ). Modeling studies and observation-based analyses have indicated that the radiative effects of these aerosols can interrupt not just localized meteorological features but also large-scale climate features such as monsoons. Using prescribed direct radiative forcing
1. Introduction Field observations in recent decades have revealed an abundance of anthropogenic aerosols, particularly absorbing aerosols, over South Asia and its surrounding ocean during the dry season ( Ramanathan et al. 2001 ). Modeling studies and observation-based analyses have indicated that the radiative effects of these aerosols can interrupt not just localized meteorological features but also large-scale climate features such as monsoons. Using prescribed direct radiative forcing
mechanisms as natural precipitation. If the quantities of water involved are similar to natural precipitation amounts, then similar mesoscale weather effects will result. Preliminary screening of the various types of human activity that add water to the environment identified three types that add water in amounts comparable to natural precipitation in the forecast area. As a result, it was hypothesized that the observed warm bias was a result of neglecting these sources of anthropogenic moisture, which
mechanisms as natural precipitation. If the quantities of water involved are similar to natural precipitation amounts, then similar mesoscale weather effects will result. Preliminary screening of the various types of human activity that add water to the environment identified three types that add water in amounts comparable to natural precipitation in the forecast area. As a result, it was hypothesized that the observed warm bias was a result of neglecting these sources of anthropogenic moisture, which
.1016/j.atmosenv.2012.12.039 . 10.1016/j.atmosenv.2012.12.039 Jiang , Y. , X. Q. Yang , and X. Liu , 2015 : Seasonality in anthropogenic aerosol effects on East Asian climate simulated with CAM5 . J. Geophys. Res. , 120 , 10 837 – 10 861 , https://doi.org/10.1002/2015JD023451 . 10.1002/2015JD023451 Kjellsson , J. , 2015 : Weakening of the global atmospheric circulation with global warming . Climate Dyn. , 45 , 975 – 988 , https://doi.org/10.1007/s00382-014-2337-8 . 10.1007/s00382
.1016/j.atmosenv.2012.12.039 . 10.1016/j.atmosenv.2012.12.039 Jiang , Y. , X. Q. Yang , and X. Liu , 2015 : Seasonality in anthropogenic aerosol effects on East Asian climate simulated with CAM5 . J. Geophys. Res. , 120 , 10 837 – 10 861 , https://doi.org/10.1002/2015JD023451 . 10.1002/2015JD023451 Kjellsson , J. , 2015 : Weakening of the global atmospheric circulation with global warming . Climate Dyn. , 45 , 975 – 988 , https://doi.org/10.1007/s00382-014-2337-8 . 10.1007/s00382
potential anthropogenic effects (e.g., due to nearby industrial or urban areas). 2. The chi-square and the balls-in-boxes tests Here, a “wet day” is defined as any day, say, the i th day in the sequence, for which the daily rainfall amount h i ≥ h t , where h t is a selected threshold. We wish to test against the null hypothesis that wet days arrive on any day of the week with equal probability . Let n k indicate the number of wet days occurring on the k th day of the week and n = ∑ 1 7 n
potential anthropogenic effects (e.g., due to nearby industrial or urban areas). 2. The chi-square and the balls-in-boxes tests Here, a “wet day” is defined as any day, say, the i th day in the sequence, for which the daily rainfall amount h i ≥ h t , where h t is a selected threshold. We wish to test against the null hypothesis that wet days arrive on any day of the week with equal probability . Let n k indicate the number of wet days occurring on the k th day of the week and n = ∑ 1 7 n
1. Introduction The annual discharge of anthropogenic aerosols into the atmosphere is considerable, but the effects of those aerosols on weather and climate remain very uncertain ( IPCC 2007 ). Aerosols can absorb and reflect solar radiation, thereby reducing the surface temperature and planetary boundary layer height, but they also act as cloud condensation nuclei (CCN) or ice nuclei, affecting cloud microphysics and subsequent precipitation rates, and increasing cloud coverage, albedo, and
1. Introduction The annual discharge of anthropogenic aerosols into the atmosphere is considerable, but the effects of those aerosols on weather and climate remain very uncertain ( IPCC 2007 ). Aerosols can absorb and reflect solar radiation, thereby reducing the surface temperature and planetary boundary layer height, but they also act as cloud condensation nuclei (CCN) or ice nuclei, affecting cloud microphysics and subsequent precipitation rates, and increasing cloud coverage, albedo, and
of research and policies aimed to “alleviate known causes of people’s vulnerability to harm, to pay attention to the distribution of risks and benefits, and to reflect on social factors that promote or discourage learning” ( Jasanoff 2007 ). In addition to mitigation, a comprehensive climate policy would require adopting adaptation strategies, not simply because of the now inevitable effects of the anthropogenic forcing, but also because of the growing risks of declining baselines of resilience
of research and policies aimed to “alleviate known causes of people’s vulnerability to harm, to pay attention to the distribution of risks and benefits, and to reflect on social factors that promote or discourage learning” ( Jasanoff 2007 ). In addition to mitigation, a comprehensive climate policy would require adopting adaptation strategies, not simply because of the now inevitable effects of the anthropogenic forcing, but also because of the growing risks of declining baselines of resilience
1. Introduction Anthropogenic aerosol is thought to play an important role in driving climate change, but its role is so complex that uncertainty in estimates of radiative forcing of climate change is dominated by uncertainty associated with forcing by anthropogenic aerosol ( Forster et al. 2007 ). This complexity arises because anthropogenic aerosol alters the planetary energy balance through a variety of mechanisms operating across a wide range of spatial scales: direct effects ( Haywood and
1. Introduction Anthropogenic aerosol is thought to play an important role in driving climate change, but its role is so complex that uncertainty in estimates of radiative forcing of climate change is dominated by uncertainty associated with forcing by anthropogenic aerosol ( Forster et al. 2007 ). This complexity arises because anthropogenic aerosol alters the planetary energy balance through a variety of mechanisms operating across a wide range of spatial scales: direct effects ( Haywood and
. This points to the need for high-resolution modeling studies that include dynamic and spatial differentiable representation of AH pattern and that can be applied in a range of urban environments. Here, to better understand the mechanism of AH impact on urban rainfall, we apply WRF to simulate summertime rainfall events in Beijing. Anthropogenic heat is simulated using the Building Effects Parameterization and Building Energy Model (BEP-BEM), which includes multilayer building
. This points to the need for high-resolution modeling studies that include dynamic and spatial differentiable representation of AH pattern and that can be applied in a range of urban environments. Here, to better understand the mechanism of AH impact on urban rainfall, we apply WRF to simulate summertime rainfall events in Beijing. Anthropogenic heat is simulated using the Building Effects Parameterization and Building Energy Model (BEP-BEM), which includes multilayer building
Climatic Research Unit temperature series since 1850 (HadCRUT3; Brohan et al. 2006 ). Because anthropogenic effects have significantly altered Earth’s climate since the start of the industrial revolution ( Solomon et al. 2007 ), we correct for these by removing estimated anthropogenic temperature change as specified by appropriately forced runs of coupled atmosphere–ocean general circulation models from the observed temperature series. The GISTEMP data were corrected using the anthropogenic
Climatic Research Unit temperature series since 1850 (HadCRUT3; Brohan et al. 2006 ). Because anthropogenic effects have significantly altered Earth’s climate since the start of the industrial revolution ( Solomon et al. 2007 ), we correct for these by removing estimated anthropogenic temperature change as specified by appropriately forced runs of coupled atmosphere–ocean general circulation models from the observed temperature series. The GISTEMP data were corrected using the anthropogenic
