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The use of fossil fuels has been a major contributor to global climate change. To mitigate the negative impact of fossil fuels, renewable energy (RE) has been increasingly promoted. This study aims to investigate factors impacting the adoption of RE in the residential sector, using the U.S. as a case study. Residential RE consumption rate data in 51 states/districts of the U.S. were collected from 2010 to 2018 to examine the adoption of RE. Correspondingly, four categories of explanatory variables affecting the consumption rate were investigated, including demographics, availability, consumers' affordability, and regulatory compliance motivation. An optimal parameters-based geographical detector (OPGD) model was implemented to investigate spatio-temporal impacts of variables on the consumption rate. Results show that factors that have consistently significant impacts on residential RE adoption include percentage of RE production of the availability category and residential monthly electricity bill of the consumers' affordability category. Population was also an important factor from 2012 to 2018. The impact of RE production rate can also be further enhanced when combined with other factors, such as residential monthly bill and number of regulatory policies. Based on these results, several practical recommendations are proposed as references for government to increase RE adoption. [ABSTRACT FROM AUTHOR]

• The carbon and water cycles of frozen soil ecosystems on the Qinghai-Tibet Plateau were analyzed. • Water use efficiency and gross primary productivity decreased progressively with stronger freezing of the frozen soil. • Evapotranspiration increased and then decreased with increasing freezing gradient. • Vegetation dominated the change in water-carbon coupling over the largest area in each permafrost type except predominantly continuous and island permafrost. The carbon and water cycle patterns of frozen soil ecosystems in regions, such as the Qinghai-Tibet Plateau (QTP), which have fragile and sensitive ecologies, are possibly affected by climate change. However, these patterns along the gradients of varying degrees of freezing remain poorly understood. In this study, we examine the spatio-temporal patterns of water use efficiency (WUE), gross primary productivity (GPP), and evapotranspiration (ET) in six frozen soil zones of the Qinghai-Tibet Plateau (QTP) with varying degrees of frozen soil. The analysis is based on the frozen soil classification criteria and remote sensing data from 2001 to 2020. The influences of six climatic, nine edaphic, and two botanic parameters on these patterns is also investigated. The results indicate that 48.05%, 24.07%, and 20% of the regions in QTP exhibit significantly upward trends of GPP, ET, and WUE, respectively. The highest increase trends were observed in GPP in the middle-thick seasonally frozen ground zone (2.36 g C m−2 yr−1), ET in the mountain permafrost zone (2.35 mm yr−1), and WUE in the predominantly continuous permafrost zone (0.003 g C kg−1 H 2 O yr−1). Meanwhile, GPP and WUE decrease progressively with the increase of freezing degrees, from the short-time frozen ground zone (GPP: 604.99 ± 51.99 g C m−2; WUE: 2.34 ± 0.15 g C kg−1 H 2 O) to the predominantly continuous permafrost zone (GPP: 114.07 ± 11.77 g C m−2; WUE: 0.33 ± 0.04 g C kg−1 H 2 O), while ET does not show significant differences across the three permafrost zones. The enhanced vegetation index is the primary factor affecting GPP and WUE in most frozen soil zones, whereas climate variables mainly impact ET. Our findings emphasize the importance of considering the effects of different freezing degrees of frozen soil when analyzing the response of the carbon and water cycles in the QTP in the context of climate change. [ABSTRACT FROM AUTHOR]