Thank you, Eric Holthaus, for your entertaining, mildly sensational climate change coverage at Slate.
In a study released Wednesday, a new estimate of how much Antarctic ice would melt in a warmer world nearly doubles previous projections of sea level rise by the end of the century. And it might be even worse than that: The study did not explore the true worst-case scenario, and its lead author said the work is still incomplete. Taken together with recent results from other research teams—most notably James Hansen’s, just last week—it’s increasingly clear that consensus projections of near-term sea level rise, about three feet in the next 85 years, are likely an underestimate.
The latest information comes via a breakthrough in simulating the behavior of Antarctica’s vast and complex network of glaciers and ice shelves. That’s brought a more complete understanding of how warmer air temperatures—projected to surpass those regularly experienced on Earth at any point during at least the last few million years—are affecting the sea level. At the same time, the study provides new certainty that—should the world act immediately to curb carbon emissions at a scale far beyond current efforts—virtually all Antarctic ice melt could be avoided.
If self-driving cars come into their own, will they reduce the total amount of vehicles on the road, or will everybody who owns a car now just buy a self-driving one? This study set in Austin says that each self-driving car will displace 9 normal cars. So even if the same or more cars are in motion at any given time, there will be a lot less land required for parking. That land can be used for something else – housing, commerce, habitat, recreation, gardening/farming, or some combination. Bring it on!
We use numerical climate simulations, paleoclimate data, and modern observations to study the effect of growing ice melt from Antarctica and Greenland. Meltwater tends to stabilize the ocean column, inducing amplifying feedbacks that increase subsurface ocean warming and ice shelf melting. Cold meltwater and induced dynamical effects cause ocean surface cooling in the Southern Ocean and North Atlantic, thus increasing Earth’s energy imbalance and heat flux into most of the global ocean’s surface. Southern Ocean surface cooling, while lower latitudes are warming, increases precipitation on the Southern Ocean, increasing ocean stratification, slowing deepwater formation, and increasing ice sheet mass loss. These feedbacks make ice sheets in contact with the ocean vulnerable to accelerating disintegration. We hypothesize that ice mass loss from the most vulnerable ice, sufficient to raise sea level several meters, is better approximated as exponential than by a more linear response. Doubling times of 10, 20 or 40 years yield multi-meter sea level rise in about 50, 100 or 200 years. Recent ice melt doubling times are near the lower end of the 10–40-year range, but the record is too short to confirm the nature of the response. The feedbacks, including subsurface ocean warming, help explain paleoclimate data and point to a dominant Southern Ocean role in controlling atmospheric CO2, which in turn exercised tight control on global temperature and sea level. The millennial (500–2000-year) timescale of deep-ocean ventilation affects the timescale for natural CO2 change and thus the timescale for paleo-global climate, ice sheet, and sea level changes, but this paleo-millennial timescale should not be misinterpreted as the timescale for ice sheet response to a rapid, large, human-made climate forcing. These climate feedbacks aid interpretation of events late in the prior interglacial, when sea level rose to +6–9 m with evidence of extreme storms while Earth was less than 1 °C warmer than today. Ice melt cooling of the North Atlantic and Southern oceans increases atmospheric temperature gradients, eddy kinetic energy and baroclinicity, thus driving more powerful storms. The modeling, paleoclimate evidence, and ongoing observations together imply that 2 °C global warming above the preindustrial level could be dangerous. Continued high fossil fuel emissions this century are predicted to yield (1) cooling of the Southern Ocean, especially in the Western Hemisphere; (2) slowing of the Southern Ocean overturning circulation, warming of the ice shelves, and growing ice sheet mass loss; (3) slowdown and eventual shutdown of the Atlantic overturning circulation with cooling of the North Atlantic region; (4) increasingly powerful storms; and (5) nonlinearly growing sea level rise, reaching several meters over a timescale of 50–150 years. These predictions, especially the cooling in the Southern Ocean and North Atlantic with markedly reduced warming or even cooling in Europe, differ fundamentally from existing climate change assessments. We discuss observations and modeling studies needed to refute or clarify these assertions.
Citation: Hansen, J., Sato, M., Hearty, P., Ruedy, R., Kelley, M., Masson-Delmotte, V., Russell, G., Tselioudis, G., Cao, J., Rignot, E., Velicogna, I., Tormey, B., Donovan, B., Kandiano, E., von Schuckmann, K., Kharecha, P., Legrande, A. N., Bauer, M., and Lo, K.-W.: Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, Atmos. Chem. Phys., 16, 3761-3812, doi:10.5194/acp-16-3761-2016, 2016.
Producing carbon nanofibers from ambient carbon dioxide seems like a potential breakthrough. You are removing the greenhouse gas from the air, and producing an incredibly useful product that can be used for everything from batteries to store renewable energy (discussed in this article) to (I am speculating) strong, light-weight carbon-negative materials that could replace a portion of the heavy-footprint steel and concrete we use today.
The cost and practicality of greenhouse gas removal processes, which are critical for environmental sustainability, pivot on high-value secondary applications derived from carbon capture and conversion techniques. Using the solar thermal electrochemical process (STEP), ambient CO2 captured in molten lithiated carbonates leads to the production of carbon nanofibers (CNFs) and carbon nanotubes (CNTs) at high yield through electrolysis using inexpensive steel electrodes. These low-cost CO2-derived CNTs and CNFs are demonstrated as high performance energy storage materials in both lithium-ion and sodium-ion batteries. Owing to synthetic control of sp3 content in the synthesized nanostructures, optimized storage capacities are measured over 370 mAh g–1 (lithium) and 130 mAh g–1 (sodium) with no capacity fade under durability tests up to 200 and 600 cycles, respectively. This work demonstrates that ambient CO2, considered as an environmental pollutant, can be attributed economic value in grid-scale and portable energy storage systems with STEP scale-up practicality in the context of combined cycle natural gas electric power generation.
Combined with renewable energy sources, maybe this is the breakthrough technology that gets us over the current hump where we are pushing against the ecological limits, and sets us on a path of continuing growth with a lower footprint until we eventually push against the limits again. Or, put the right incentives and policies in place to control the unsustainable portion of the growth, and with this technology in place maybe we can make it all the way until the asteroid hits. And by then, we can try to have people spread across a few planets. And then we are good until the sun burns out, or the aliens come for us, or the universe collapses. None of which will be my problem.
This thoughtful opinion piece in Trends in Ecology and Evolution talks about resolving conflicts between moral and economic arguments for conservation.
Biodiversity exists at multiple levels of organization, including at the levels of genes, populations, species, and ecosystems [11]. Although it might be argued that intrinsic value is associated with all levels of biological organization, this interpretation is of no practical use for planning and decision-making. If all levels of biological organization have equal intrinsic value, and if all species are regarded as having equal intrinsic value, then the implication is that no harm can be done in any way to any component of biodiversity [I don’t quite follow this last sentence…]. The concept of intrinsic value applied equally to all of nature therefore offers no way to prioritize and points only toward a halt to human progress because most human developments impact on nature to some degree. In practice, then, intrinsic value is commonly associated with certain species and ecosystems…
Species conservation and the beauty of nature are reasons for conservation commonly associated with intrinsic and non-use values. For instance, it can be regarded as morally right to maintain the existence of tigers in the wild, and to conserve the beauty of Yosemite Valley, regardless of human use. But accepting this should not preclude accepting arguments for conservation that are based on utilitarian value, particularly when we consider different levels of biological organization. For instance, populations of species provide vital ecosystem services such as pollination, such that loss of a population can cause loss of an ecosystem service that has utilitarian value. If the continued existence of populations of the species elsewhere means that the species itself is not threatened, or if the population lives in a human-dominated, non-wild landscape, then arguments for the intrinsic value of species and ecosystems are inadequate. Given that population declines are perhaps the most prevalent aspect of biodiversity loss [14], failure to recognize the utilitarian value of populations does a disservice to conservation.
Viewing reasons for conserving nature at different levels of biological organization thus clarifies when alternative arguments are most relevant, in particular that arguments based on intrinsic value are most commonly associated with species and ecosystem levels. This takes us some way toward melding utilitarian and intrinsic reasons for conservation, enabling both to be included within a multifaceted approach.
The article also wades into the debate on monetization.
I agree with using all the tools. We also have to recognize that even reasonable people have a range of values, and there are also unreasonable people out there, and we have to find arguments that appeal to a critical mass of people in order to make any progress.
Here’s a green roof modeling study from Singapore. Green roofs reduce peak flows enough to help with flooding. They reduce the volume of runoff a little bit through increased evapotranspiration, which would have an effect on the water supply in Singapore where urban runoff is used as a water source.
Low-impact development (LID) comprises a broad spectrum of stormwater management technologies for mitigating the impacts of urbanization on hydrological processes. Among these technologies, green roofs are one of the most adopted solutions, especially in densely populated metropolitan areas, where roofs take up a significant portion of the impervious surfaces and land areas are scarce. While the in situ hydrological performance of green roofs—i.e., reduction of runoff volume and peak discharge—is well addressed in literature, less is known about their impact on stormwater management and reuse activities at a catchment or city scale. This study developed an integrated urban water cycle model (IUWCM) to quantitatively assess the effect of uniform green roof deployment (i.e., 25, 50, and 100% conversion of traditional roofs) over the period 2009–2011 in the Marina Reservoir catchment, a 100-km2100-km2, highly urbanized area located in the heart of Singapore. The IUWCM consists of two components: (1) a physically based model for extensive green roofs integrated within a one-dimensional numerical hydrological-hydraulic catchment model linked with (2) an optimization-based model describing the operation of the downstream, stormwater-fed reservoir. The event-based hydrological performance of green roofs varied significantly throughout the simulation period with a median of about 5% and 12% for the catchment scale reduction of runoff volume and peak discharge (100% conversion of traditional roofs). The high variability and lower performance (with respect to temperate climates) are strongly related to the tropical weather and climatic conditions—e.g., antecedent dry weather period and maximum rainfall intensity. Average annual volume reductions were 0.6, 1.2, and 2.4% for the 25, 50, and 100% green roof scenarios, respectively. The reduction of the stormwater generated at the catchment level through green roof implementation had a positive impact on flood protection along Marina Reservoir shores and the energy costs encountered when operating the reservoir. Vice versa, the drinking water supply, which depends on the amount of available stormwater, decreased due to the evapotranspiration losses from green roofs. Better performance in terms of stormwater reuse could only be obtained by increasing the time of concentration of the catchment. This may be achieved through the combination of green roofs with other LID structures.
The urban water system is a complex adaptive system consisting of technical, environmental and social components which interact with each other through time. As such, its investigation requires tools able to model the complete socio-technical system, complementing “infrastructure-centred” approaches. This paper presents a methodology for integrating two modelling tools, a social simulation model and an urban water management tool. An agent based model, the Urban Water Agents’ Behaviour, is developed to simulate the domestic water users’ behaviour in response to water demand management measures and is then coupled to the Urban Water Optioneering Tool to calculate the evolution of domestic water demand by simulating the use of water appliances. The proposed methodology is tested using, as a case study, a major period of drought in Athens, Greece. Results suggest that the coupling of the two models provides new functionality for water demand management scenarios assessment by water regulators and companies.
I had never thought about modeling tree canopy volume in 3D before. I’ve played around with simple algorithms to place trees on a map, assume a mature canopy area per tree, and estimate the total canopy area. This is useful because cities sometimes set targets and metrics in terms of number of trees, and sometimes in terms of tree canopy. The latter is better because it is more relatable to other goals a city might have related to the hydrologic cycle, carbon, heat, air quality, aesthetics and property values, biodiversity and habitat, and the financial cost to public offers of achieving these goals. Once you have an algorithm relating number of trees to canopy area, you can add more variables like type of tree, growth over time, and some assumed attrition rate or half life. Come to think of it, I have played around with leaf area index which is a quasi-3D concept. Anyway, without further ado here is the article that prompted my line of thought:
The aim of this research is to quantify the local impacts of tree volumes on the nocturnal urban heat island intensity (UHI). Volume of each individual tree is estimated through a 3D tree model dataset derived from LIDAR data and modelled with geospatial technology. Air temperature is measured on 103 different locations of the city on a relatively warm summer night. We tested an empirical model, using multi-linear regression analysis, to explain the contribution of tree volume to UHI while also taking into account urbanization degree and sky view factor at each location. We also explored the scale effect by testing variant radii for the aggregated tree volume to uncover the highest impact on UHI. The results of this study indicate that, in our case study area, tree volume has the highest impact on UHI within 40 meters and that a one degree temperature reduction is predicted for an increase of 60,000 m3 tree canopy volume in this 40 meter buffer. In addition, we present how geospatial technology is used in automating data extraction procedures to enable scalability (data availability for large extents) for efficient analysis of the UHI relation with urban elements.
More theoretical knowledge on science communication can provide useful background knowledge for geoscience communicators, and thereby positively contribute to the geoscience debate in society. With this latter goal in mind, in this paper, we provide geoscientists with a review of relevant general science communication the- 5 ory. We focus on television appearances of (geo)scientists, though much of the research/themes/literature discussed also holds for popular-scientific presentations or for interactions with newspaper journalists. We use the term television loosely, also applying it to programs that appear online.
In this review we discuss six major themes in science communication research 10 related to television performances: scientist motivation (Sect. 2), target audience (Sect. 3), jargon and information transfer (Sect. 4), narratives and storytelling (Sect. 5), relationship between scientists and journalists (Sect. 6), and stereotypes of scientists (Sect. 7). For each theme we make the results from the literature tangible by analyzing a television appearance of a geoscientist from a science communication perspective. 15 For these case studies we use examples for which we had background information on behind-the-scenes discussions and negotiations, namely television appearances of authors Hut and Stoof.
Connecting science, policy, and implementation for landscape-scale habitat connectivity
In an increasingly fragmented world, networks of habitat corridors are critical to support movement of organisms between habitat patches and the long-term persistence of species. The science of corridor design and the policy of corridor establishment are developing rapidly, but often independently. Here we assess the links between the science and policy of habitat corridors, to better understand how corridors can be effectively implemented, with a focus on a suite of landscape-scale connectivity plans in tropical and sub-tropical Asia. Our synthesis suggests that the process of corridor designation may be more efficient if the scientific determination of optimal corridor locations and arrangement is synchronized in time with the achievement of political buy-in and policy direction for corridor designation. Land tenure and the intactness of existing habitat in the region are also critical factors –optimal connectivity strategies may be very different if there are few, versus many, political jurisdictions (including commercial and traditional land tenures) and intact versus degraded habitat between patches. We identify financing mechanisms for corridors, and also several important gaps in our understanding of effective corridor design including how corridors, particularly those managed by local communities, can be protected from habitat degradation and unsustainable hunting. Finally, we point to a critical need for quantitative, data-driven models that can prioritize potential corridors or multi-corridor networks based on their relative contributions to long-term metacommunity persistence.