Moisture recycling is the atmospheric branch of the water cycle, including evaporation and precipitation. While the physical water cycle is well-understood, the social links among the recipients of precipitation back to the sources of evaporation are not. In this work, we develop a method to determine how these social connections unfold, using a mix of quantitative and qualitative methods, finding that there are distinct types of social connections with corresponding policy and management tools. Hide

The 100 year GWP is the most widely used metric for comparing the climate impact of different gases such as methane and carbon dioxide. However, there have been recent arguments for the use of different timescales. This paper uses straightforward estimates of future damages to quantitatively determine the appropriate timescale as a function of how society discounts the future, and finds that the 100 year timescale is consistent with commonly used discount rates. Hide

Results show that an additional 6.97 million people will be exposed to droughts in China under 1.5 °C target relative to reference period, mostly in the east side of Hu line. Demographic change is the primary contributor to exposure. Moderate droughts contribute the most to exposure among three droughts. Our simulations suggest that drought impact on people will continue to be a large threat to China under 1.5 °C target. It will be helpful in guiding adaptation and mitigation strategies. Hide

The paper examines the assertion that limits to growth in the renewable energy sector can be inferred statistically from historical data for installed capacity of solar and wind power. This claim has been made in the peer reviewed scientific literature and has been subject to considerable media coverage. It is demonstrated here that rational selection between an exponential and a logistic growth model cannot be made from existing data for the historical evolution of global installed capacity. Hide

Long-term variations in the Siberian river discharges of the Lena in the east and the Ob in the west were investigated based on observations, tree-ring reconstructions and simulations with atmospheric and climate models. In conclusion, an east–west seesaw pattern of summertime large-scale atmospheric circulation frequently emerges over Siberia as an atmospheric internal variability, resulting in the negative correlation between the Lena and Ob River discharges. Hide

Limiting global warming to 1.5 °C may require carbon removal from the atmosphere. We explore how the climate system differs when we achieve the 1.5 °C limit by rapid emissions reductions versus when we overshoot this limit, hitting 2 °C at mid-century before removing CO₂ from the atmosphere. Using a model, we show that sea level, ocean acidification, regional warming, and ocean circulation are very different under the overshoot pathway at 2100, despite hitting the 1.5 °C target for surface warming. Hide

We study the impact of uncertainty on optimal greenhouse gas (GHG) emission policies for a stylized emission problem. The results suggest that uncertainties about the implementability of decisions on emission reductions (or increases) call for more precautionary policies. In contrast, uncertainties about the implications of exceeding critical cumulated emission thresholds tend to make early emission reductions less rewarding. Hide

Cultural processes are underrepresented in Earth system models although they decisively shape humanity's planetary imprint. We set forth ideas on how Earth system analysis can be enriched by formalising aspects of religion (understood broadly as a collective belief in things held sacred). We sketch possible modelling avenues (extensions of existing Earth system models and new coevolutionary models) and suggest research primers to explicate and quantify mental aspects of the Anthropocene. Hide

A key question in climate science is how the global mean surface temperature responds to changes in greenhouse gases. This dependency is quantified by the climate sensitivity, which is determined by the complex feedbacks in the climate system. In this study we use observations of past climate change to estimate this sensitivity. Our estimate is consistent with values for the equilibrium climate sensitivity estimated by complex climate models, but sensitive to the use of input data. Hide

Using climate simulations, we investigate the role of water recycling in shaping the climate of low-obliquity Earth-like terra-planets. By such a mechanism feeding water back from the extra-tropics to the tropics, the planet can assume two drastically different climate states differing by more than 35 K in global temperature. We describe the bifurcation between the two states occurring upon changes in surface albedo and argue that the bi-stability hints to a wider habitable zone for such planets. Hide

It has been shown that regional temperature and precipitation changes in future climate-change scenarios often scale quasi-linearly with global mean temperature change (∆GMT). We show that an important consequence of these physical climate changes, namely changes in agricultural crop yields, can also be described in terms of ∆GMT to a large extent. This makes it possible to efficiently estimate future crop yield changes for different climate-change scenarios without need for complex models. Hide

For many complex social-ecological systems, robustness and resilience are difficult to quantify and the connections and trade-offs between them difficult to study. In this study, we present an analytical framework to address the linkage between robustness and resilience more systematically. The results reveal the tradeoffs between robustness and resilience. They also show how the nature of such tradeoffs varies with the choices of certain policies internal stresses and external disturbances. Hide

The paper investigates variability of the gravity wave drag in the stratosphere in connection with climate phenomena like El Niño-Southern oscillation. This link represents a possible mechanism of the tropospheric influence on the higher atmospheric layers – mechanism of utmost importance that has not been studied in details yet. The results illustrates that there are indeed significant changes of the gravity wave drag distribution and strength depending on the phase of the studied oscillations. Hide

In austral spring 2016 the Antarctic region experienced anomalous sea ice retreat in all sectors, with sea ice extent in October and November 2016 being the lowest in the Southern Hemisphere over the observational record (1979–present). The extreme sea ice retreat was accompanied by the wettest and warmest spring on record, over large areas covering the Indian ocean, the Ross Sea and the Weddell Sea. Hide