There is broad consensus that scientists in working on innovative, highly socially impactful areas of innovation have moral responsibilities toward stakeholders and the general public. However, there is widespread disagreement concerning the nature of their responsibilities or their implications for scientific research. In this dissertation, I address scientists' social responsibilities when performing innovative research on a particularly novel and impactful kind of technology: climate engineering. Climate engineering, as a technology, poses many ethical, political, and scientific problems. I focus on a particular issue in early-stage climate engineering research: such research could embed controversial ethical and political values and priorities into climate engineering technologies, leading to the imposition of values on non-consenting populations. It is the responsibility of scientists, therefore, to ensure the values they use in climate engineering research are morally and politically legitimate. In the first half of the dissertation, I consider a broad range of possible solutions to the problem, but standard political and ethical frameworks fail, I argue, to provide scientists the resources to adequately discharge this responsibility. In the second half of dissertation, I turn to a framework that provides alternative theoretical resources for legitimating scientific values in innovative climate engineering research. This framework analyzes the science of climate engineering as composed of multiple overlapping practices, with virtues internal to each practice. I argue that, as a condition for scientific values to be legitimate, they must arise in communities of practice marked by virtue, that is, communities that are composed of (and, in turn, foster) virtuous actors and behaviors. I explore characteristics of such communities, analyzing them as consisting in practices integrated into larger, robust conceptions of flourishing in relation to the biosphere as a whole. While endorsing a moderate pluralism with regard to the conceptions of flourishing that climate engineering research communities could work with, I delineate a number of virtues clearly characteristic of the ethical climate engineering researcher. In my final chapter, I offer some practical guidance as to how virtuous climate engineering research communities can be fostered.