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Glacial and fluvial landforms record the recent history of Earth’s surface, and hold information on the climatic or tectonic processes that shape the landscape. Southern Patagonia hosts uniquely well-preserved fluvial cut-and-fill terraces. A record of fluvial incision since 1.5–4 Ma is preserved from K-Ar dated basalt flows atop relict paleosurfaces, and published regional thermochronometric dating and modelling suggest an increased phase of exhumation in the last 1–3 Ma. However, few constraints exist on the onset of river incision, which might provide clues as to possible drivers of regional landscape change. To constrain the timing of Pleistocene incision and landscape evolution in southern Patagonia, we present new cosmogenic 10Be exposure ages of surface cobbles and amalgamated pebbles from fluvial terraces in the Tres Lagos region 50ºS) and the Río Santa Cruz. Locally, dated basalt flows set a maximum age of ~2.2 Ma for the Tres Lagos terraces, and between 2.2 and 1.7 Ma in the Condor Cliffs region of the Río Santa Cruz. Preliminary 10Be ages for terrace surfaces in the Tres Lagos region reveal ages between 45–845 ka. Ages of upstream fluvial terraces of the Río Santa Cruz reveal ages between 290–830 ka. The sequence of terrace ages shows that the phase of net incision started ca. 1 Ma after widespread emplacement of basalts, concomitant with enhanced climatic forcing following the Mid-Pleistocene Transition. Ages are also in agreement with the incision history recorded in dated fluvial terraces of other Patagonian rivers, notably the Río Deseado, where ages range from 400 ka–1 Ma (47ºS; Tobal et al., 2021). We argue that the combined results suggest that this net-incisional phase was widespread, therefore unlikely to result from local tectonic drivers, hence probably climatically driven. Our record of Pleistocene landscape evolution is similar to other records throughout the Andes, where the timing of fluvial incision has been linked with the transition to enhanced climatic forcing after ~1 Ma (e.g., Central Andes). Our results point a strong influence of the Mid-Pleistocene Transition on landscape evolution on a continental scale, and notably also in the southernmost regions of South America.

Alluvial surfaces like fluvial terraces can act as markers for past changes in sediment and water flux along alluvial rivers. By precisely dating terrace surfaces, we can begin to quantify how sedimentary signals propagate though river channels and better infer the paleo-climatic and tectonic conditions during their formation. However, collecting and processing geochronological samples along larger river systems can be costly and time consuming. Here, we extend alluvial landform age control along the Río Santa Cruz of southern Patagonia by applying a spectral surface characteristic model calibrated from a limited set of field samples and cosmogenic nuclide derived exposure ages. This quantitative method leverages the spectral response of surface weathering to ultimately improve age control of the region's fluvial landforms while reducing the time and cost associated with traditional field dating methods.Ages of alluvial surfaces may correlate with time-dependent geochemical weathering processes, such as clay mineral formation. Although previous surface-weathering studies have mostly focused on surface ages since the last or penultimate glaciation, we analyzed the change in weathering state for southern Patagonian fluvial terraces up to a million years old consisting of quarzitic and granitic source lithologies. We find that multispectral Landsat 8 data show a 20% increase in the band 6 to band 2 ratio with terrace elevation (and inferred age), highlighting the higher reflectance in the shortwave infrared band often associated with clay mineral formation. It is likely that weathering rates in the dry and cold Patagonian environment are slower compared to regions with less stable and warmer climate conditions or lithological sources, where age dependent weathering signals in multispectral data tend to saturate on much shorter time scales. Our new 10Be results from surface cobbles and amalgamated pebbles yield exposure ages roughly between 45 and 1000 ka for these surfaces, and the calibrated spectral model allows us to interpolate ages of additional 9 alluvial surface generations based on 11 dated surfaces in the region.Planned in-situ spectral surface measurements will provide robust ground-truthing to the satellite-based observations and allow for further investigation of the mineral changes driving the age-dependent spectral signal. Furthermore, additional terraces will be dated downstream to provide (1) a better understanding of how the weathering process may differ with downstream distance, and (2) a more reliable correlation of surfaces over long distances (> 100 km), enabling us to reconstruct the details of past climate forcing on alluvial-channel evolution.

Nighttime light emissions are increasing in most countries worldwide, but which types of lighting are responsible for the increase remains unknown. Also unknown is what fraction of outdoor light emissions and associated energy use are due to public light sources (i.e. streetlights) or various types of private light sources (e.g. advertising). Here we show that it is possible to measure the contribution of street lighting to nighttime satellite imagery using ‘smart city’ lighting infrastructure. The city of Tucson, USA, intentionally altered its streetlight output over 10 days, and we examined the change in emissions observed by satellite. We find that streetlights operated by the city are responsible for only 13% of the total radiance (in the 500–900 nm band) observed from Tucson from space after midnight (95% confidence interval 10–16%). If Tucson did not dim their streetlights after midnight, the contribution would be 18% (95% confidence interval 15–23%). When streetlights operated by other actors are included, the best estimates rise to 16% and 21%, respectively. Existing energy and lighting policy related to the sustainability of outdoor light use has mainly focused on street lighting. These results suggest an urgent need for consideration of other types of light sources in outdoor lighting policy.

There is a knowledge gap concerning the identification and quantification of transported soil particles in subsurface flows. If these soil particles reach relevant amounts, protective measures against soil erosion applied on the surface may be partially ineffective, and the soil may degrade further and unnoticed. In consequence, there is a need to develop a method to determine this subsurface particle transport in situ. A laboratory flume experiment was developed to examine the processes of fine soil material transport as well as the development of sediment traps for in situ measurements. Since, steep-slope vineyard soils are especially prone to subsurface flows they were subject of first investigations: The shallow steep-slope vineyard soils of the Mosel wine region are mainly developed from Devonian argillaceous schists and Pleistocene terrace sediments. Among the main physical characteristics are a very high rock fragment content and a loose surface layer over a strongly compacted layer caused by the combined action of tillage and weathering. This structure is presumably prone to subsurface flows within the upper horizon, especially in periods of very high soil moisture. The results of this laboratory experiment clearly confirm the presence of subsurface particle transport and the applicability of a sediment trap prototype consisting of a relatively simple and low-cost drain structure.

The Mosel wine region (Rhineland-Palatinate, Germany) is the largest steep vineyard region in the world. Due to extreme slopes, tillage with heavy machinery, increase in extreme precipitation events, and new planting of vines, these vineyards are among the agricultural systems most affected by soil erosion.As a result of viticulture since the Roman period and their special characteristics, almost all vineyard soils in the Mosel region are classified as Terric Anthrosols. These soils are characterized by a very high rock fragment content (mainly Devonian argillaceous schists and fluvial sediments) and a loose surface horizon over a compact one due to tillage or weathered parent material. This structure enables subsurface flows within the upper horizon, especially in periods of very high soil moisture.There is a knowledge gap concerning the identification and quantification of transported soil particles in this subsurface flow. If these soil particles reach relevant amounts, superficial protective measures against soil erosion may be partially ineffective, and the soil degrades due to substantial loss of fine material. In consequence, there is a need to develop a method to determine this subsurface particle transport in situ.In this study, a first experimental approach for assessing the occurrence of subsurface erosion of fine-grained soil particles within soils is presented. Using this experimental set-up, it is possible to prove the process of fine soil material transport as well as the development of sediment traps for in situ measurements.The experimental approach consists of a sediment trap prototype, based on a drainage pipe, which is positioned into a test flume. The dimensions of this flume are 2.7 m x 0.9 m x 0.2 m (L x W x H). It is filled with material from a vineyard soil of the Mosel valley flanks. Water enters the flume from the upper end with the help of an 0.11 m high overflow. The sediment trap is 0.86 m long and has an 0.855 m x 0.4 m long side-cut-out where a mesh (mesh aperture 3 mm x 6 mm) is installed. It is connected to a separate drain where the water and eroded sediment are collected. This is analysed in the laboratory to quantify the amount and characteristics of the eroded material. Additionally, the total subsurface flow is measured by a drain at the lower end of the soil body for having a total mass budget of runoff and erosion.The preliminary results show a clear correlation between the measured total subsurface flow and sediment transport with the ones collected with the sediment trap. The results suggest that this sediment trap prototype is clearly suitable to quantify the subsurface soil erosion. In the further course of the work, the sediment trap will be installed in situ in the vineyards to test its field applicability to determine valid subsurface erosion rates in vineyard soils.

The architecture of the avant-garde was based on its practitioners’ certitude of having come up with an alternative to what was already there: a plan for a better world. With what Lyotard called the end of the great narratives, architecture lost this certainty and the utopia left behind was scorched earth. But in a development that went generally unnoticed at first, a new generation of visionaries began to tend this wasteland. Today, their field is abloom with the “retropia” of New Urbanism, which purports to redeem Modernism’s unfulfilled pledge of a better life in the post-historical present of an eternal yesterday. To this extent, New Urbanism is the de facto heir of the avant-garde, and not the least of the reasons why is that it can lay absolutely uncontested claim today to the public popularity that the avant-garde had postulated in rather prophylactic fashion back in its day. Thus, the topos of utopia is already occupied and no longer available to contemporary architecture, which has no alternative than to deal with the status quo. Architects — assuming that intervening in reality is even on their agenda — must face it and come to terms with it. Accordingly, it’s not “Fuck …” but rather “Face the Context” that becomes their motto. To do so, they have to renounce the avant-garde’s bipolar worldview in which architecture rides in like the good guy in the white hat to deliver society from the evils besetting it. That all-toofamiliar sermon preaching replacement of the conventional Old by the progressive New now gives way to a practice of mutation whereby it is precisely that which already exists that constitutes the material for its own renewal

Die Architektur von heute ist dem Prinzip des Ikonischen verfallen. Ikone oder NichtIkone, das schien die Frage fur immer mehr Architekten und, in noch starkerem Ausmas, auch fur ihre Auftraggeber zu sein. Dieses Streben nach Ikonizitat verweist auf eine subtile Machtverschiebung weg von der Stadt hin zur Architektur.