Estimated cloud-top entrainment index explains positive low-cloud-cover feedback.

How subtropical marine low cloud cover (LCC) will respond to global warming is a major source of uncertainty in future climate change. Although the estimated inversion strength (EIS) is a good predictive index of LCC, it has a serious limitation when applied to evaluate LCC changes due to warming: The LCC decreases despite increases in EIS in future climate simulations of global climate models (GCMs). In this work, using state-of-the-art GCMs, we show that the recently proposed estimated cloud-top entrainment index (ECTEI) decreases consistently with LCC in warmer sea surface temperature (SST) climates. For the patterned SST warming predicted by coupled GCMs, ECTEI can constrain the subtropical marine LCC feedback to -0.41 ± 0.28% K-1 (90% CI), implying virtually certain positive feedback. ECTEI physically explains the heuristic model for LCC changes based on a linear combination of EIS and SST changes in previous studies in terms of cloud-top entrainment processes.

The impact of parametrized convection on cloud feedback.

We investigate the sensitivity of cloud feedbacks to the use of convective parametrizations by repeating the CMIP5/CFMIP-2 AMIP/AMIP + 4K uniform sea surface temperature perturbation experiments with 10 climate models which have had their convective parametrizations turned off. Previous studies have suggested that differences between parametrized convection schemes are a leading source of inter-model spread in cloud feedbacks. We find however that 'ConvOff' models with convection switched off have a similar overall range of cloud feedbacks compared with the standard configurations. Furthermore, applying a simple bias correction method to allow for differences in present-day global cloud radiative effects substantially reduces the differences between the cloud feedbacks with and without parametrized convection in the individual models. We conclude that, while parametrized convection influences the strength of the cloud feedbacks substantially in some models, other processes must also contribute substantially to the overall inter-model spread. The positive shortwave cloud feedbacks seen in the models in subtropical regimes associated with shallow clouds are still present in the ConvOff experiments. Inter-model spread in shortwave cloud feedback increases slightly in regimes associated with trade cumulus in the ConvOff experiments but is quite similar in the most stable subtropical regimes associated with stratocumulus clouds. Inter-model spread in longwave cloud feedbacks in strongly precipitating regions of the tropics is substantially reduced in the ConvOff experiments however, indicating a considerable local contribution from differences in the details of convective parametrizations. In both standard and ConvOff experiments, models with less mid-level cloud and less moist static energy near the top of the boundary layer tend to have more positive tropical cloud feedbacks. The role of non-convective processes in contributing to inter-model spread in cloud feedback is discussed.

Relationship Between Insomnia and Continued Outpatient Treatment in Psychiatric Patients.

Purpose: Sleep plays an essential role in maintaining both physical and mental well-being. Many patients in psychiatric outpatient settings complain of insomnia. However, the causal relationship between insomnia and depressive symptoms in all mental illnesses remains unclear. Moreover, research on insomnia and the continuation of outpatient treatment is lacking. We hypothesize a high correlation between depression and insomnia among patients with diverse mental illnesses. Additionally, we posit that insomnia significantly influences the continuity of outpatient visits. To this end, we evaluated insomnia and depression symptoms in psychiatric patients both at their initial visit and one year later. We also examined factors related to insomnia at the outset and factors associated with the ongoing utilization of outpatient treatment. Patients and Methods: The participants of the study consisted of patients who made their first visit to the outpatient department of psychiatry and neurology at Showa University East Hospital between June 1, 2021, and March 31, 2023, and who continued attending the outpatient clinic for one year. Clinical characteristics were assessed using the Self-rating Depression Scale (SDS) and the Athens Insomnia Scale (AIS). Results: The study's findings were collected from a cohort of 1106 patients and revealed that more than 70% experienced insomnia at the time of their initial visit. In total 137 patients continued to receive outpatient treatment for one year, and their AIS scores improved from 9 points to 5 points. A multivariate analysis revealed that the SDS items of depressed mood and insomnia were confounding factors influencing AIS improvement. Conclusion: Given that 70% of patients complained of insomnia at the time of their first visit and that sleep improved in many of the 12.4% of patients who continued to receive outpatient treatment for at least one year, the results suggest that sleep status is an important determinant of whether a patient continues to attend outpatient clinics.