Abstract

Mammals have dominated Earth for approximately 55 Myr thanks to their adaptations and resilience to warming and cooling during the Cenozoic. All life will eventually perish in a runaway greenhouse once absorbed solar radiation exceeds the emission of thermal radiation in several billions of years. However, conditions rendering the Earth naturally inhospitable to mammals may develop sooner because of long-term processes linked to plate tectonics (short-term perturbations are not considered here). In ~250 Myr, all continents will converge to form Earth’s next supercontinent, Pangea Ultima. A natural consequence of the creation and decay of Pangea Ultima will be extremes in due to changes in volcanic rifting and outgassing. Here we show that increased , solar energy (F⨀; approximately +2.5% W m−2 greater than today) and continentality (larger range in temperatures away from the ocean) lead to increasing warming hostile to mammalian life. We assess their impact on mammalian physiological limits (dry bulb, wet bulb and Humidex heat stress indicators) as well as a planetary habitability index. Given mammals’ continued survival, predicted background levels of 410–816 ppm combined with increased F⨀ will probably lead to a climate tipping point and their mass extinction. The results also highlight how global landmass configuration, and F⨀ play a critical role in planetary habitability.

Abstract

Global aviation emissions have been growing despite international efforts to limit climate change. Quantifying the status quo of domestic and international aviation emissions is necessary for establishing an understanding of current emissions and their mitigation. Yet, a majority of the United Nations framework convention on climate change (UNFCCC)-ratifying parties have infrequently disclosed aviation emissions within the international framework, if at all. Here, we present a set of national aviation emission and fuel burn inventories for these 197 individual parties, as calculated by the high-resolution aviation transport emissions assessment model (AviTeam) model. In addition to CO2 emissions, the AviTeam model calculates pollutant emissions, including NOx, SOx, unburnt hydrocarbons, black carbon, and organic carbon. Emission inventories are created in aggregated and gridded format and rely on Automatic Dependent Surveillance–Broadcast combined with schedule data. The cumulative global fuel burn is estimated at 291 Tg for the year 2019. This corresponds to CO2 emissions of 920 Tg, with 306 Tg originating from domestic aviation. We present emissions from 151 countries that have yet to report their emissions for 2019, which sum to 417 TgCO2. The improved availability of national emissions data facilitated by this inventory could support mitigation efforts in developed and developing countries and shows that such tools could bolster sector reporting to the UNFCCC.

A power substation near a data center in Ashburn, Virginia. Photographer: Nathan Howard/Bloomberg By Josh Saul

May 2, 2024 at 5:10 PM UTC

Data center developers in Northern Virginia are asking utility Dominion Energy Inc. for as much power as several nuclear reactors can generate, in the latest sign of how artificial intelligence is helping drive up electricity demand. Dominion regularly fields requests from developers whose planned data center campuses need as much as “several gigawatts” of electricity, Chief Executive Officer Bob Blue said Thursday during the company’s first-quarter earnings call. A gigawatt is roughly the output of a nuclear reactor and can power 750,000 homes. Electric utilities are facing the biggest demand jump in a generation. Along with data centers to run AI computing, America’s grid is being strained by new factories and the electrification of everything from cars to home heating. The surge in demand is complicating utility efforts to turn off carbon-emitting power plants and meet their climate goals.

Over the past five years, Dominion has connected 94 data centers that, together, consume about four gigawatts of electricity, Blue said. That means that just two or three of the data center campuses now being planned could require as much electricity as all the centers Dominion hooked up since about 2019.

(kinda) A great website to share if you have no idea how to explain the downfall of the US economy.

Edit: Thanks to everyone who provided insight on this website. I've had this in my bookmarks for a very long time and was curious how it held up.

Abstract The Neolithic revolution saw the independent development of agriculture among at least seven unconnected hunter-gatherer populations. I propose that the rapid spread of agricultural techniques resulted from increased climatic seasonality causing hunter-gatherers to adopt a sedentary lifestyle and store food for the season of scarcity. Their newfound sedentary lifestyle and storage habits facilitated the invention of agriculture. I present a model and support it with global climate data and Neolithic adoption dates, showing that higher seasonality increased the likelihood of agriculture’s invention and its speed of adoption by neighbors. This study suggests that seasonality patterns played a dominant role in determining our species’ transition to farming.

On the path to climate neutrality, global production and trade of basic materials might change due to the heterogeneous availability of renewable electricity. Here we estimate the “renewables pull”, i.e. the energy-cost savings associated with such relocation, for varying depths of relocation for three key tradable energy-intensive industrial commodities: steel, urea, and ethylene. Assuming an electricity-price difference of 40 EUR/MWh, we find respective relocation savings of 19%, 33%, and 38%, which might, despite soft factors in the private sector, lead to green relocation. Conserving today's production patterns by importing hydrogen is substantially costlier, whereas imports of intermediate products could be almost as cost-efficienct, while keeping substantial value creation in importing regions. A societal debate on macroeconomic, industrial, and geopolitical implications is needed, potentially resulting in selective policies of green-relocation protection.

Significance

Humans become increasingly fragile as they age. We show that something similar may happen to states, although for states, the risk of termination levels off as they grow older, allowing some to persist for millennia. Proximate causes of their demise such as conquest, coups, earthquakes, and droughts are easy to spot and have received significant attention. However, our results suggest that unraveling what shapes resilience to such events is equally important if we are to understand state longevity and collapse. Risk of termination rises over the first 200 y, inviting a search for mechanisms that can undermine resilience at this timescale.

Abstract

How states and great powers rise and fall is an intriguing enigma of human history. Are there any patterns? Do polities become more vulnerable over time as they age? We analyze longevity in hundreds of premodern states using survival analysis to help provide initial insights into these questions. This approach is commonly used to study the risk of death in biological organisms or failure in mechanical systems. The results reveal that the risk of state termination increased steeply over approximately the first two centuries after formation and stabilized thereafter. This provides the first quantitative support for the hypothesis that the resilience of political states decreases over time. Potential mechanisms that could drive such declining resilience include environmental degradation, increasing complexity, growing inequality, and extractive institutions. While the cases are from premodern times, such dynamics and drivers of vulnerability may remain relevant today.

Abstract

Effective policies to halt biodiversity loss require knowing which anthropogenic drivers are the most important direct causes. Whereas previous knowledge has been limited in scope and rigor, here we statistically synthesize empirical comparisons of recent driver impacts found through a wide-ranging review. We show that land/sea use change has been the dominant direct driver of recent biodiversity loss worldwide. Direct exploitation of natural resources ranks second and pollution third; climate change and invasive alien species have been significantly less important than the top two drivers. The oceans, where direct exploitation and climate change dominate, have a different driver hierarchy from land and fresh water. It also varies among types of biodiversity indicators. For example, climate change is a more important driver of community composition change than of changes in species populations. Stopping global biodiversity loss requires policies and actions to tackle all the major drivers and their interactions, not some of them in isolation.

Homo sapiens has evolved to reproduce exponentially, expand geographically, and consume all available resources. For most of humanity’s evolutionary history, such expansionist tendencies have been countered by negative feedback. However, the scientific revolution and the use of fossil fuels reduced many forms of negative feedback, enabling us to realize our full potential for exponential growth. This natural capacity is being reinforced by growth-oriented neoliberal economics

https://youtu.be/yJvczRkQHK0?si=sKeNgDa3ked5kafS