Abstract A major step towards achieving the goals of the Paris agreement would be a measurable change in the evolution of global warming in response to mitigation of anthropogenic emissions. The inertia and internal variability of the climate system, however, will delay the emergence of a discernible response even to strong, sustained mitigation. Here, we investigate when we could expect a significant change in the evolution of global mean surface temperature after strong mitigation of individual climate forcers. Anthropogenic CO 2 has the highest potential for a rapidly measurable influence, combined with long term benefits, but the required mitigation is very strong. Black Carbon (BC) mitigation could be rapidly discernible, but has a low net gain in the longer term. Methane mitigation combines rapid effects on surface temperature with long term effects. For other gases or aerosols, even fully removing anthropogenic emissions is unlikely to have a discernible impact before mid-century.

AbstractEvapotranspiration (ET) is a major component linking the water, energy, and carbon cycles. Understanding changes in ET and the relative contribution rates of human activity and of climate change at the basin scale is important for sound water resources management. In this study, changes in ET in the Heihe agricultural region in northwest China during 1984–2014 were examined using remotely-sensed ET data with the Soil and Water Assessment Tool (SWAT). Correlation analysis identified the dominant factors that influence change in ET per unit area and those that influence change in total ET. Factor analysis identified the relative contribution rates of the dominant factors in each case. The results show that human activity, which includes factors for agronomy and irrigation, and climate change, including factors for precipitation and relative humidity, both contribute to increases in ET per unit area at rates of 60.93% and 28.01%, respectively. Human activity, including the same factors, and climate change, including factors for relative humidity and wind speed, contribute to increases in total ET at rates of 53.86% and 35.68%, respectively. Overall, in the Heihe agricultural region, the contribution of human agricultural activities to increased ET was significantly greater than that of climate change.

Ocean-onto-land droughts (OTLDs)—i.e., droughts originating over the oceans and migrating onto land—are a recently identified phenomenon with severe natural and human impacts. However, the influence of anthropogenic emissions on past and future changes in OTLDs and their underlying mechanisms remain unclear. Here, using precipitation-minus-evaporation deficits to identify global OTLDs, we find OTLDs have intensified due to anthropogenic climate change during the past 60 years. Under a future high-emissions scenario, the OTLDs would become more frequent (+39.68%), persistent (+54.25%), widespread (+448.92%), and severe (+612.78%) globally. Intensified OTLDs are associated with reduced moisture transport driven by subtropical anticyclones in the northern hemisphere and complex circulation patterns in the southern hemisphere. The reduction in moisture transport during OTLDs is mainly caused by the atmospheric thermodynamic responses to human-induced global warming. Our results underscore the importance of improving understanding of this type of drought and adopting climate mitigation measures.

Over the past two centuries, anthropogenic stress and climate change have blurred understanding of their individual and combined impacts on lake ecosystems. This study analyzed 477 ecological shifts documented in 224 paleolimnological records from lakes to trace their responses to climate change and anthropogenic stressors over time. By classifying ecological shifts according to their primary drivers (anthropogenic stress, climatic change, or their combined effects), this study characterized how lake ecosystems respond to these pressures. Stress response analysis revealed that climate‐driven responses predominated during post‐Little Ice Age warming, whereas anthropogenic stress became the dominant factor by the early 20th century, accompanied by the onset of the 2nd Industrial Revolution. While the Great Acceleration initiated widespread ecological shifts in lakes globally through synergistic interactions between anthropogenic activities and climate change, anthropogenic stress may still exert a greater impact on these shifts than climate change. Spatial analysis revealed divergent responses across lake ecosystems across the globe, though representation was limited from the Southern Hemisphere and tropical regions. Temperate lakes are highly susceptible to anthropogenic stressors; Arctic lakes have heightened sensitivity to climate change; and alpine lakes have coupled responses to both drivers. The cumulative response index developed in this study isolates individual stressors temporally, revealing substantial impacts of historical human development on lake ecosystems. These effects leave persistent signatures preserved in sedimentary archives, providing new perspectives on drivers of ecological trajectories across temporal scales.

causes climate change, feedbacks combine to control climate sensitivity to that forcing. While the overall sum of feedbacks is negative, it is becoming Climate change feedbacks are natural processes that impact how much global temperatures will increase for a given amount of greenhouse gas emissions. Positive feedbacks amplify global warming while negative feedbacks diminish it. Feedbacks influence both the amount of greenhouse gases in the atmosphere and the amount of temperature change that happens in response. While emissions are the forcing t Following Le Chatelier's principle, the chemical equilibrium of the Earth's carbon cycle will shift in response to anthropogenic CO2 emissions. The primary driver of this is the ocean, which absorbs anthropogenic CO2 via the so-called solubility pump. At present this accounts for only about one third of the current emissions, but ultimately most (~75%) of the CO2 emitted by human activities will dissolve in the ocean over a period of centuries: "A better approximation of the lifetime of fossil fuel CO2 for public discussion might be 300 years, plus 25% that lasts forever". However, the rate at which the ocean will take it up in the future is less certain, and will be affected by stratification induced by warming and, potentially, changes in the ocean's thermohaline circulation. It is believed that the single largest factor in determining the total strength of the global carbon sink is the state of the Southern Ocean - particularly of the Southern Ocean overturning circulation.

Ovule and seed development of crop plants in response to climate change The ovule is a plant structure that upon fertilization, transforms into a seed. Successful fertilization is required for optimum crop productivity and is strongly affected by environmental conditions including temperature and precipitation. Climate change refers to sustained changes in global or regional climate patterns over an extended period, typically decades to millions of years. These shifts can result from natural processes like volcanic eruptions and solar radiation fluctuations, but in recent times, human activities—especially the burning of fossil fuels, deforestation, and industrial emissions—have accelerated the pace and scale of climate change. Human-induced climate change impacts the agricultural sector mainly through global warming and altering weather patterns, both of which create conditions that challenge agricultural production and food security. With food demand projected to sharply increase by 2050, urgent action is needed to prevent the worst impacts of climate change on food security and allow time for agricultural production systems to adapt and become more resilient.

tons/ha/yr.°! A sustainable rate of soil loss (rate of soil loss is equal to rate of soil formation) is thought … increasing at the rate of 0.5% per year; CH, currently at 1.74 ppm and increasing at the rate of 0.75% per … interactive effects of climate, vegetation, relief, parent material, time, and the human activities. Soils have

to occur at the rate E,. When C is less than S., the rate is assumed to be ECS . The rate of change of … more intense floods and droughts) and the rate of climate change is likely to be substantially greater than … to mitigate climate change. i: The Science of Climate Change 1.1 The Variability of Climate Variations