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Anthropogenic activities have drastically impacted the climate system since the Industrial Revolution. However, to what extent anthropogenic emissions influence the cloud droplet number concentration (Nd), the critical parameter for understanding aerosol‐cloud interactions, is poorly known on the hemispheric scale due to the considerable retrieval uncertainty. We employed multiple widely used Nd retrieval sampling methods to evaluate the long‐term trend in Nd contrast (ΔNd(NH‐SH)) between the Northern Hemisphere (NH) and Southern Hemisphere (SH). Here we show that the ΔNd(NH‐SH) was halved from 2003 to 2020 using different sampling methods and channels, even though the range of magnitudes of ΔNd(NH‐SH) from different retrieval sampling methods is large. Such dramatic changes in ΔNd(NH‐SH) are dominated by the significantly decreased Nd over the NH (∼20%) due to emission reductions compared to the relatively stable and pristine nature of the SH. Aerosol optical depth (AOD) and aerosol index (AI) correlate poorly with Nd based on long‐term trends, even though they replicate the contrast trends. This poor correlation is partly contributed by stratospheric smoke from wildfires in Australia that had little influence on Nd in the SH. The northwest Atlantic shows the largest contribution, ∼38%, to the Nd trend, whereas the northwest Pacific dominates the change in AOD and AI, contributing more than 60% to AOD and ∼50% to the AI trend in the NH. Our results imply that emission reductions significantly reduced ΔNd(NH‐SH) and provide strong observational evidence that anthropogenic activities have extensively altered liquid clouds in the NH in the last two decades. Plain Language Summary: Cloud droplet number concentration (Nd) is essential in understanding cloud physics, precipitation formation, and quantifying the effective radiative forcing associated with aerosol‐cloud interactions. Under the background of emission reductions over the past two decades, this study used global satellite observations to explore the long‐term (2003–2020) trend in Nd over the ocean and its hemispheric contrast (ΔNd(NH‐SH)) between the Northern Hemisphere and Southern Hemisphere. We found that Nd decreased ∼20% over the Northern Hemisphere, but no clear Nd trend was found over the Southern Hemisphere. As a result, the fractional change (defined as the trend divided by its climatology) of ΔNd(NH‐SH) is about −60% from 2003 to 2020. We further quantify the regional contribution and found that the northwest Atlantic shows the largest contribution, ∼38%, to the Nd trend over the Northern Hemisphere. Our results provide strong observational evidence that anthropogenic activities have extensively modified the microphysical properties of liquid clouds in the Northern Hemisphere over the past two decades. Key Points: The interhemispheric contrast of cloud droplet number concentration (Nd) was halved during 2003–2020 mainly due to emission reductionsAlthough Aerosol optical depth (AOD) and aerosol index (AI) replicated the contrast trends, they correlate poorly with NdIn the Northern Hemisphere, the northwest Atlantic contributes the most to Nd long‐term change, whereas the northwest Pacific dominates the AOD/AI trend [ABSTRACT FROM AUTHOR]

This article contributes to the emerging theory of industry belief systems and the social construction of innovation by examining how industry actors conceptualise and negotiate industry transformation through the development and diffusion of new technologies. In a qualitative study of innovation in the Australian wool industry, we found that the social construction of industry belief systems and new technologies was an evolutionary process of social sensemaking in which there was reciprocity between individual and collective meaning-making that reflected conflict, consensus and compliance between industry actors about new technologies and industry beliefs. [ABSTRACT FROM AUTHOR]

Abstract: Since the 1970s, the Australian government has seen the information and communication technology industry as a viable industry for promotion and investment. This paper will argue that two recent important policy initiatives that concern the information and communication technology industry are influenced by the idea of an impending post-industrial economy and observations of the business environment of Silicon Valley. It will firstly discuss a policy initiative towards investment funding through the creation of ‘incubators’ that is informed by early-age liability theories of organisation. It will secondly discuss the policy initiative towards replicating the business environment of Silicon Valley through the creation of technology parks that is informed by the paradigm of locational economics. It will be shown that despite the positive contributions to the economy that policy interventions in the information and communication technology industry has had, the replication of the business environment of Silicon Valley in Australia should be attempted with caution. [Copyright &y& Elsevier]