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Climate change is predicted to intensify lake algal blooms globally and result in regime shifts. However, observed increases in algal biomass do not consistently correlate with air temperature or precipitation, and evidence is lacking for a causal effect of climate or the nonlinear dynamics needed to demonstrate regime shifts. We modeled the causal effects of climate on annual lake chlorophyll (a measure of algal biomass) over 34 y for 24,452 lakes across broad ecoclimatic zones of the United States and evaluated the potential for regime shifts. We found that algal biomass was causally related to climate in 34% of lakes. In these cases, 71% exhibited abrupt but mostly temporary shifts as opposed to persistent changes, 13% had the potential for regime shifts. Climate was causally related to algal biomass in lakes experiencing all levels of human disturbance, but with different likelihood. Climate causality was most likely to be observed in lakes with minimal human disturbance and cooler summer temperatures that have increased over the 34 y studied. Climate causality was variable in lakes with low to moderate human disturbance, and least likely in lakes with high human disturbance, which may mask climate causality. Our results explain some of the previously observed heterogeneous climate responses of lake algal biomass globally and they can be used to predict future climate effects on lakes. 

Existing academic structures and norms perpetuate the mistreatment and marginalization of scholars resulting in a climate that is misaligned with the values of academics from marginalized groups. Therefore, we study how climates at multiple levels of the academy (i.e., research group, department, and professional field) shape marginalized scholars’ careers and career attitudes. Participants (N = 3,204) were doctoral students, postdoctoral fellows, and assistant professors from four science fields (biology, physics, economics, and psychology) who completed an online survey about psychological safety and intragroup conflict within their research group, climate of diversity within their department, climate of scholarly inclusion within their professional field, and their career outcomes. We conducted three general structural equation models with marginalized identity status predicting three career outcomes: turnover intentions, burnout disengagement, and burnout exhaustion. We also tested the mediation effect of climate at the levels of the research group, department, and profession on these career outcomes. Participants with a greater number of marginalized identities experienced a more negative climate at all three levels compared to those with no and fewer marginalized identities. The climate experienced at these three levels also significantly mediated all three career outcomes for marginalized scholars. Climate of scholarly inclusion at the level of the profession was especially strongly related to intent to leave and burnout. These results add to the breadth of research on multiply marginalized scholars’ negative experiences of academic climates and point to areas that may be particularly important for interventions. 

Abstract AimWe aimed to measure the dominant spatial patterns in ecosystem properties (such as nutrients and measures of primary production) and the multi‐scaled geographical driver variables of these properties and to quantify how the spatial structure of pattern in all of these variables influences the strength of relationships among them. Location and time periodWe studied > 8,500 lakes in a 1.8 million km²area of Northeast U.S.A. Data comprised 10‐year medians (2002–2011) for measured ecosystem properties, long‐term climate averages and recent land use/land cover variables. Major taxa studiedWe focused on ecosystem properties at the base of aquatic food webs, including concentrations of nutrients and algal pigments that are proxies of primary productivity. MethodsWe quantified spatial structure in ecosystem properties and their geographical driver variables using distance‐based Moran eigenvector maps (dbMEMs). We then compared the similarity in spatial structure for all pairs of variables with the correlation between variables to illustrate how spatial structure constrains relationships among ecosystem properties. ResultsThe strength of spatial structure decreased in order for climate, land cover/use, lake ecosystem properties and lake and landscape morphometry. Having a comparable spatial structure is a necessary condition to observe a strong relationship between a pair of variables, but not a sufficient one; variables with very different spatial structure are never strongly correlated. Lake ecosystem properties tended to have an intermediary spatial structure compared with that of their main drivers, probably because climate and landscape variables with known ecological links induce spatial patterns. Main conclusionOur empirical results describe inherent spatial constraints that dictate the expected relationships between ecosystem properties and their geographical drivers at macroscales. Our results also suggest that understanding the spatial scales at which ecological processes operate is necessary to predict the effects of multi‐scaled environmental changes on ecosystem properties.