Collapse

Abstract

The Greenland Ice Sheet (GrIS) meltwater runoff has increased considerably since the 1990s, leading to implications for the ice sheet mass balance and ecosystem dynamics in ice-free areas. Extreme weather events will likely continue to occur in the coming decades. Therefore, a more thorough understanding of the spatiotemporal patterns of extreme melting events is of interest. This study aims to analyze the evolution of extreme melting events across the GrIS and determine the climatic factors that drive them. Specifically, we have analyzed extreme melting events (90th percentile) across the GrIS from 1950 to 2022 and examined their links to the surface energy balance (SEB) and large-scale atmospheric circulation. Extreme melting days account for approximately 35%–40% of the total accumulated melting per season. We found that extreme melting frequency, intensity, and contribution to the total accumulated June–August (summer) melting show a statistically significant upward trend at a 95% confidence level. The largest trends are detected across the northern GrIS. The trends are independent of the extreme melting percentile rank (90th, 97th, or 99th) analyzed and are consistent with average melting trends that exhibit an increase in similar magnitude and spatial configuration. Radiation plays a dominant role in controlling the SEB during extreme melting days. The increase in extreme melting frequency and intensity is driven by the increase in anticyclonic weather types during summer and more energy available for melting. Our results help to enhance the understanding of extreme events in the Arctic.

>Humanity’s rapacious consumption is more than Earth and its climate can handle, which is driving an ecological crisis.

Hurricane Helene’s ‘historic flooding’ made worse by global heating, Fema says

Helene aftermath: At least 92 dead, severe flood risk remains

Historic North Carolina village underwater after devastating damage from Helene

'We're desperate': Mexico's Acapulco relives hurricane nightmare - One year after Otis

This Japanese region is still recovering from a deadly earthquake. Now record rains have flooded its streets

Edit: I forgot to post links about Nepal.

At least 193 killed, 100 injured in flooding and landslides in Nepal

Nepal floods and landslides death toll passes 200, reports say

Abstract

Scientific evidence has documented we are undergoing a mass extinction of species, caused by human activity. However, allocating conservation resources is difficult due to scarce evidence on damages from losing individual species. This paper studies the collapse of vultures in India, triggered by the expiry of a patent on a painkiller. Our results suggest the functional extinction of vultures—efficient scavengers that removed carcasses from the environment—increased human mortality by over 4 percent because of a large negative shock to sanitation. We quantify damages at $69.4 billion per year. These results suggest high returns to conserving keystone species such as vultures

Abstract

Background

Over 1800 food contact chemicals (FCCs) are known to migrate from food contact articles used to store, process, package, and serve foodstuffs. Many of these FCCs have hazard properties of concern, and still others have never been tested for toxicity. Humans are known to be exposed to FCCs via foods, but the full extent of human exposure to all FCCs is unknown. Objective

To close this important knowledge gap, we conducted a systematic overview of FCCs that have been monitored and detected in human biomonitoring studies according to a previously published protocol.

Methods

We first compared the more than 14,000 known FCCs to five biomonitoring programs and three metabolome/exposome databases. In a second step, we prioritized FCCs that have been frequently detected in food contact materials and systematically mapped the available evidence for their presence in humans.

Results

For 25% of the known FCCs (3601), we found evidence for their presence in humans. This includes 194 FCCs from human biomonitoring programs, with 80 of these having hazard properties of high concern. Of the 3528 FCCs included in metabolome/exposome databases, most are from the Blood Exposome Database. We found evidence for the presence in humans for 63 of the 175 prioritized FCCs included in the systematic evidence map, and 59 of the prioritized FCCs lack hazard data.

Significance

Notwithstanding that there are also other sources of exposure for many FCCs, these data will help to prioritize FCCs of concern by linking information on migration and biomonitoring. Our results on FCCs monitored in humans are available as an interactive dashboard (FCChumon) to enable policymakers, public health researchers, and food industry decision-makers to make food contact materials and articles safer, reduce human exposure to hazardous FCCs and improve public health.

>Pandemics – the global spread of infectious diseases – seem to be making a comeback. In the Middle Ages we had the Black Death (plague), and after the first world war we had the Spanish flu. Tens of millions of people died from these diseases.

>Then science began to get the upper hand, with vaccination eradicating smallpox, and polio nearly so. Antibiotics became available to treat bacterial infections, and more recently antivirals as well.

>But in recent years and decades pandemics seem to be returning. In the 1980s we had HIV/AIDS, then several flu pandemics, SARS, and now COVID (no, COVID isn’t over).

>So why is this happening, and is there anything we can do to avert future pandemics?

But can you mine without fossil fuels and fossil-derived materials? How much materials do you need to mine to first transition and then maintain the infrastructure? Can you maintain renewable just with renewable? Taking progressively lower grade ores? What do you do with growing volume of tailings?

Such articles are more than a bit misleading.

Abstract

Waste heat production represents an inevitable consequence of energy conversion as per the laws of thermodynamics. Based on this fact, by using simple theoretical models, we analyze constraints on the habitability of Earth-like terrestrial planets hosting putative technological species and technospheres characterized by persistent exponential growth of energy consumption and waste heat generation: in particular, we quantify the deleterious effects of rising surface temperature on biospheric processes and the eventual loss of liquid water. Irrespective of whether these sources of energy are ultimately stellar or planetary (e.g., nuclear, fossil fuels) in nature, we demonstrate that the loss of habitable conditions on such terrestrial planets may be expected to occur on timescales of ≲1000 years, as measured from the start of the exponential phase, provided that the annual growth rate of energy consumption is of order 1%. We conclude by discussing the types of evolutionary trajectories that might be feasible for industrialized technological species, and sketch the ensuing implications for technosignature searches.

Abstract

Human populations tend to grow steadily, because of the ability of people to make innovations, and thus overcome and extend the limits imposed by natural resources. It is therefore questionable whether traditional concepts of population ecology, including environmental carrying capacity, can be applied to human societies. The existence of carrying capacity cannot be simply inferred from population time-series, but it can be indicated by the tendency of populations to return to a previous state after a disturbance. So far only indirect evidence at a coarse-grained scale has indicated the historical existence of human carrying capacity. We analysed unique historical population data on 88 settlements before and after the Thirty Years War (1618–1648), one the longest and most destructive conflicts in European history, which reduced the population of Central Europe by 30–50%. The recovery rate of individual settlements after the war was positively correlated with the extent of the disturbance, so that the population size of the settlements after a period of regeneration was similar to the pre-war situation, indicating an equilibrium population size (i.e. carrying capacity). The carrying capacity of individual settlements was positively determined mostly by the fertility of the soil and the area of the cadastre, and negatively by the number of other settlements in the surroundings. Pre-industrial human population sizes were thus probably controlled by negative density dependence mediated by soil fertility, which could not increase due to limited agricultural technologies.

Abstract

Climate models indicate that dry extremes will be exacerbated in many regions of the world1,2. However, confidence in the magnitude and timing of these projected changes remains low3,4, leaving societies largely unprepared5,6. Here we show that constraining model projections with observations using a newly proposed emergent constraint (EC) reduces the uncertainty in predictions of a core drought indicator, the longest annual dry spell (LAD), by 10–26% globally. Our EC-corrected projections reveal that the increase in LAD will be 42–44% greater, on average, than ‘mid-range’ or ‘high-end’ future forcing scenarios currently indicate. These results imply that by the end of this century, the global mean land-only LAD could be 10 days longer than currently expected. Using two generations of climate models, we further uncover global regions for which historical LAD biases affect the magnitude of projected LAD increases, and we explore the role of land–atmosphere feedbacks therein. Our findings reveal regions with potentially higher- and earlier-than-expected drought risks for societies and ecosystems, and they point to possible mechanisms underlying the biases in the current generation of climate models.

Abstract

Over the last 70 years, extreme heat has been increasing at a disproportionate rate in Western Europe, compared to climate model simulations. This mismatch is not well understood. Here, we show that a substantial fraction (0.8 °C [0.2°−1.4 °C] of 3.4 °C per global warming degree) of the heat extremes trend is induced by atmospheric circulation changes, through more frequent southerly flows over Western Europe. In the 170 available simulations from 32 different models that we analyzed, including 3 large model ensembles, none have a circulation-induced heat trend as large as observed. This can be due to underestimated circulation response to external forcing, or to a systematic underestimation of low-frequency variability, or both. The former implies that future projections are too conservative, the latter that we are left with deep uncertainty regarding the pace of future summer heat in Europe. This calls for caution when interpreting climate projections of heat extremes over Western Europe, in view of adaptation to heat waves.

Abstract

Individual coral polyps contain three distinct components—the surface mucus layer, tissue, and skeleton; each component may exhibit varying extent of microplastic (MP) accumulation and serve as a short- or long-term repository for these pollutants. However, the literature on MP accumulation in wild corals, particularly with respect to the different components, is limited. In this study, we investigated the adhesion and accumulation of MPs in four coral species, including both large (Lobophyllia sp. and Platygyra sinensis) and small (Pocillopora cf. damicornis and Porites lutea) polyp corals collected from Si Chang Island in the upper Gulf of Thailand. The results revealed that MP accumulation varied significantly among the four coral species and their components. Specifically, P. cf. damicornis exhibited the highest degree of accumulation (2.28 ± 0.34 particles g−1 w.w.) [Tukey's honestly significant difference (HSD) test, p < 0.05], particularly in their skeleton (52.63 %) and with a notable presence of high-density MPs (Fisher's extract test, p < 0.05). The most common MP morphotype was fragment, accounting for 75.29 % of the total MPs found in the coral. Notably, the majority of MPs were black, white, or blue, accounting for 36.20 %, 15.52 %, and 11.49 % of the samples, respectively. The predominant size range of MP particles was 101–200 μm. Nylon, polyacetylene, and polyethylene terephthalate (PET) were the prevalent polymer types, accounting for 20.11 %, 14.37 %, and 9.77 % of the identified samples, respectively. In the large polyp corals, while MP shapes, colors, and sizes exhibited consistent patterns, remarkable differences were noted in the polymer types across the three components. The findings of this study improve the understanding of MP accumulation and its fate in coral reef ecosystems, underscoring the need for further investigation into MP-accumulation patterns in reef-building corals worldwide.

>Researchers from Japan and Thailand investigating microplastics in coral have found that all three parts of the coral anatomy—surface mucus, tissue, and skeleton—contain microplastics. The findings were made possible thanks to a new microplastic detection technique developed by the team and applied to coral for the first time. > > These findings may also explain the "missing plastic problem" that has puzzled scientists, where about 70% of the plastic litter that has entered the oceans cannot be found. The team hypothesizes that coral may be acting as a "sink" for microplastics by absorbing it from the oceans. Their findings were published in the journal Science of the Total Environment. > > [...] > > As for types of microplastics, the team found that nylon, polyacetylene, and polyethylene terephthalate (PET) were the three most prevalent, accounting for 20.11%, 14.37%, and 9.77%, respectively, of the identified samples.

Abstract

Twenty years after the first publication using the term microplastics, we review current understanding, refine definitions and consider future prospects. Microplastics arise from multiple sources including tires, textiles, cosmetics, paint and the fragmentation of larger items. They are widely distributed throughout the natural environment with evidence of harm at multiple levels of biological organization. They are pervasive in food and drink and have been detected throughout the human body, with emerging evidence of negative effects. Environmental contamination could double by 2040 and widescale harm has been predicted. Public concern is increasing and diverse measures to address microplastics pollution are being considered in international negotiations. Clear evidence on the efficacy of potential solutions is now needed to address the issue and to minimize the risks of unintended consequences.

Abstract

Reducing uncertainty in the response of the Amazon rainforest, a vital component of the Earth system, to future climate change is crucial for refining climate projections. Here we demonstrate an emergent constraint (EC) on the future response of the Amazon carbon cycle to climate change across CMIP6 Earth system models. Models that overestimate past global warming trends, tend to estimate hotter and drier future Amazon conditions, driven by northward shifts of the intertropical convergence zone over the Atlantic Ocean, causing greater Amazon carbon loss. The proposed EC changes the mean CMIP6 Amazon climate-induced carbon loss estimate (excluding CO2 fertilisation and land-use change impacts) from −0.27 (−0.59–0.05) to −0.16 (−0.42–0.10) GtC year−1 at 4.4 °C warming level, reducing the variance by 34%. This study implies that climate-induced carbon loss in the Amazon rainforest by 2100 is less than thought and that past global temperature trends can be used to refine regional carbon cycle projections.

Abstract

A long-term record of global mean surface temperature (GMST) provides critical insight into the dynamical limits of Earth’s climate and the complex feedbacks between temperature and the broader Earth system. Here, we present PhanDA, a reconstruction of GMST over the past 485 million years, generated by statistically integrating proxy data with climate model simulations. PhanDA exhibits a large range of GMST, spanning 11° to 36°C. Partitioning the reconstruction into climate states indicates that more time was spent in warmer rather than colder climates and reveals consistent latitudinal temperature gradients within each state. There is a strong correlation between atmospheric carbon dioxide (CO2) concentrations and GMST, identifying CO2 as the dominant control on variations in Phanerozoic global climate and suggesting an apparent Earth system sensitivity of ~8°C.

Global average surface temperatures shattered all-time records in 2023 at 1.45 ± 0.12 °C above pre-industrial levels (WMO 2024). Worsened by climate change-induced drought, Canadian wildfires burned 18.5 million hectares, nearly three-times more land area than in any previous year on record (NRC 2023). Parts of the Amazon River reached their lowest levels in 120 years of data-keeping and, in places, recorded surface water temperatures near 40 °C (Rodrigues 2023). The world has reached the threshold of a 1.5 °C increase in global average surface temperature and is only beginning to experience the full consequences.

Methane (CH4) is the second most important anthropogenic greenhouse gas after carbon dioxide. It contributed 0.5 °C of warming in the 2010s relative to the late 1800s—two-thirds as much warming as CO2 (IPCC 2021). It is also far more potent than CO2 ton for ton, with a global warming potential (GWP) >80 and 30 times more than CO2 for the first twenty years and century after release, respectively (Forster et al 2021).

Methane is rising faster in relative terms than any major greenhouse gas and is now 2.6-fold higher than in pre-industrial times. Global average methane concentrations reached 1931 parts per billion (ppb) in January of 2024 (Lan et al 2024). Annual increases in methane are also accelerating for reasons that are debated. Global methane concentrations rose by 15, 18, 13, and 10 ppb each year from 2020 through 2023, respectively, the second, first, fourth, and fourteenth largest increases since the U.S. National Oceanic and Atmospheric Administration (NOAA) methane time series began in 1983 (Lan et al 2024).

The Global Carbon Project updates its Global Methane Budget (GMB) every few years (Saunois et al 2016, 2020, 2024). The GMB integrates results of: (1) bottom-up (BU) estimates based on process-based models for estimating wetland surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations, and (2) top-down (TD) CH4 emission estimates based on atmospheric observations and an inverse-modeling framework. Here, we summarize new estimates of the GMB based on the new GMB (Saunois et al 2024). We estimate CH4 sources and sinks for the periods 2000–2002 and 2018–2020, as well as for the most-recent year (2020), the last year that full global TD and BU methane datasets are available. We compare 3 year-average estimates to smooth the inter-annual variability signals from climatic variability such as the El Niño-Southern Oscillation (ENSO) that influence natural emissions from wetlands and other ecosystems, as well as from the chemical sink.

We provide insights on data for methane sources and sinks globally and for the geographical regions and economic sectors whose emissions have changed the most since 2000. We also provide additional data on changes in recent years using satellite-based inversions using the TROPOspheric Monitoring Instrument (TROPOMI) (e.g. Yu et al 2023).