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Rocky Mountain National Park contains a dense record of prehistoric Native American archaeological locales and biological resources, but questions remain about the past use of the Park’s ice patches by ancient humans and animals. Our survey of 30 locations in the Park revealed that the majority of ice patches are small in size and contain limited evidence of past visitation by mobile peoples, but moderate use by game. In this paper, we present new radiocarbon dates for materials documented in the recently melted forefield of the ROMO 9 ice patch, a mid-sized ice body located in alpine tundra along the Continental Divide. Dated materials include timber-sized pine trees, keratin and bone collagen from large game (bighorn sheep, elk), and a possible wooden artifact made from Mountain mahogany. Results suggest most finds date to several periods of known neoglaciation, during the mid-Holocene (c. 4150 cal BP) and the Little Ice Age (c. 115 cal BP). Our results corroborate past findings on mid-Holocene timberline in the Colorado Front Range, as well as the paucity of archaeological evidence from small ice patches in Colorado.

The tribe Stenochiini Kirby, 1837 comprises six genera in North America with most species occurring in the tropical and temperateregions of the continent. Only two species in the genus Strongylium Kirby, 1818 have previously been reported from west of theContinental Divide in the United States from Arizona and New Mexico and no members of the tribe have been reported from the stateof Sonora, Mexico. We here report Strongylium tenuicolle (Say, 1826), known to be widely distributed east of the Rocky Mountains,from west of the Continental Divide for the first time from both Arizona and New Mexico. We similarly report the first records ofboth Strongylium apache Triplehorn and Spilman, 1973 and Strongylium atrum Champion, 1888 from Sonora. Oploptera chamelensis(Doyen, 1990) was previously known only from the type series from Jalisco, Mexico and is here reported from Sonora, which thereby extends the known range of this genus significantly. To promote consistency in generic recognition, we propose the transfer of Oploptera simplicicollis (LeConte, 1878) New Combination from Strongylium for the species distributed across the southeastern United States. Species diagnoses are given, and generic boundaries are discussed along with the expected diversity of the Sonoran Desert region.

Detailed topographic map evidence and a new Cenozoic geologic and glacial history paradigm are used to determine the previously unexplained Yampa River-Colorado River drainage divide origin. The Yampa River now flows in a north direction away from the Colorado River (between the Park Range to the east and the Flat Tops region to the west) before turning in a west direction to reach the Unita Mountains where it joins the south-oriented Green River, which eventually joins the southwest-oriented Colorado River. Topographic maps show the Yampa-Colorado River drainage divide is asymmetric with steeper slopes leading to the Colorado River, barbed (south-oriented) tributaries leading to north-oriented Yampa River headwaters (especially near the Yampa River turn to the west), and evidence of a large north-to-south oriented diverging and converging channel complex that preceded present-day drainage routes. Map evidence is interpreted to mean massive south-oriented floods flowed through what are now north-oriented Yampa River headwaters valleys and that headward erosion of a deep west-oriented valley beheaded and reversed those south-oriented flood flow channels to create the north-oriented Yampa River headwaters and the Egeria Park area Yampa-Colorado River drainage divide seen today. Large south-oriented floods leading to the Colorado River (while regional uplift was occurring) are inconsistent with accepted Cenozoic geologic and glacial history paradigm predictions, but are predicted by a newly proposed Cenozoic geologic and glacial history paradigm in which a thick continental ice sheet created a deep “hole” by eroding underlying bedrock and also by causing crustal warping that raised the present-day northern Colorado east-west continental divide as immense south-oriented meltwater floods flowed across it.

The history of what the title of Baghramian and Marchetti’s book refers to as the ‘Great Divide’ between Analytic and Continental philosophy has been the subject of much debate and controversy in r...

Contemporary Western philosophy has been generally perceived as one that encompasses two divergent traditions of philosophical thought: analytic and continental. A number of writers have drawn attention to the difficulty of explaining the differences between them. A small number of authors have even questioned the credibility of the analytic-continental division. In this paper I argue that the gulf between traditions is real and has a negative impact on three elements of education in Croatia: philosophy as an academic subject, students and university professors. Before delving into the aforementioned issue, I briefly specify areas of philosophical inquiry where the gulf is the most evident. I end paper with several suppositions concerning the future path of both traditions, which are mostly based on the idea of cooperation between analytic and continental philosophers as it would profoundly contribute to the advancement of teaching philosophy.

Costa Rica is known as a verdant, tropical paradise with rich rainforests, abundant wildlife, striking mountains and volcanoes, and picturesque beaches. However, the perceived abundance of Costa Rica’s water resources is only true for part of the country. The same geography and climate that bring abundant precipitation to most of southern Costa Rica and its Caribbean coast also leave the northern Pacific province of Guanacaste with substantially less rainfall and even periods of severe drought. This case study focuses on Guanacaste province, which is a major tourist destination as well as one of the country’s most productive agricultural regions. Water from the lush Caribbean slopes of the Lake Arenal region is transported across the continental divide through extensive infrastructure projects. Passing through the semi-arid regions of Guanacaste, hydroelectric power generation, extensive irrigated agriculture, and tourism development use most of the water, supporting a rapidly growing regional economy but leaving increasingly less water for environmental flows. This case study introduces students to “nexus thinking” to explore the multiple and overlapping water, energy, and food (WEF) demands and ecological challenges present in Guanacaste province. Each sector and its interconnections with other sectors are examined in turn through introductory lectures, and enriched by WEF systems thinking activities and class discussions. At the conclusion of this case study curriculum, students will be able to identify and characterize points of intersection, i.e., the nexus, of WEF supply and demand, and trade-offs that exist between WEF resources and biodiversity conservation.

A new and fundamentally different regional geomorphology paradigm in which massive south- and southeast-oriented meltwater floods flowed across the entire Missouri River drainage basin is tested by interpreting detailed topographic maps of the Montana upper Sun River drainage basin region by trying to explain origins of previously unexplained or poorly explained erosional landforms located upstream from Sun River Canyon (which cuts across Montana’s north-to-south oriented Sawtooth Range). Mountain passes, through valleys, and other drainage divide low points along what are today high mountain ridges, including the North American east-west continental divide, are interpreted to be evidence of drainage routes that once crossed the region. These drainage divide crossings suggest that prior to erosion of present-day upper Sun River drainage basin valleys, massive floods moved in south directions across what are today the north-oriented Middle and South Fork Flathead River drainage basins into today’s upper Sun River drainage basin area and carved a complex of diverging and converging channels into what was probably a low relief surface now represented by the crests of the region’s highest mountain ridges. Further, the map evidence shows how a diverging complex of south- and southeast-oriented upstream Sun River drainage basin flood flow channels changed flow direction to cross the Sawtooth Range in a northeast direction before converging on the Montana plains at a location downstream from Sun River Canyon. The observed upper Sun River drainage basin area topographic map evidence is consistent with the new geomorphology paradigm predictions, in which massive south-oriented meltwater floods flowing across the rising rim of a continental ice sheet created deep “hole” (created by deep ice sheet erosion and ice sheet weight caused crustal warping) are diverted to flow in northeast and north directions into and across deep “hole” space being opened up by ice sheet melting.

P ymatuning Swamp lies buried beneath Pymatuning Reservoir, subdued but not forgotten, its legacy still visible in the hydric soils and wetlands of the reservoir backwaters (figure 1). This is a story of a changing climate, melting glaciers, ancient lakes filled with sediments, swamplands of northwestern Pennsylvania, and humanity's unceasing efforts to mold and manage the natural landscape for human uses. The footprint of the Adena culture, hunters and gatherers who grew corn ( Zea mays L.), beans, and squash 3,000 to 1,000 years ago near the wetlands, was light. Their settlements thrived for a short period along Pymatuning Creek, the Shenango River, and Conneaut Lake swamp. By the late 1700s, Europeans attempted to settle the wet, forested region incentivized by the Pennsylvania Land Act. The human solution to this wetland wilderness of abundant white pine ( Pinus strobus ), beaver ( Castor canadensis ), and wildlife that was nearly impenetrable to travel was to construct the Beaver to Erie Canal in the 1830s. This extension of the Erie Canal connected the Ohio River via Beaver River north to Shenango River, over the continental divide to Lake Erie and quickened the transport and exchange of the wilderness's raw materials and East Coast's dry goods. The Pymatuning…

The continental divide along the spine of the Canadian Rockies in southwestern Canada is a critical headwater region for hydrological drainages to the Pacific, Arctic, and Atlantic oceans. Major flooding events are typically attributed to heavy precipitation on its eastern side due to upslope (easterly) flows. Precipitation can also occur on the western side of the divide when moisture originating from the Pacific Ocean encounters the west-facing slopes of the Canadian Rockies. In other storms, substantial precipitation can fall on both sides. Meteorological data over this critical region are sparse, with few stations located at high elevations. Given the importance of all these types of events, the Storms and Precipitation Across the continental Divide Experiment (SPADE) was initiated to enhance our knowledge of the atmospheric processes leading to storms and precipitation on either side of the continental divide. This was accomplished by installing specialized meteorological instrumentation on both sides of the continental divide and carrying out manual observations during an intensive field campaign from 24 April–26 June 2019. On the eastern side, there were two field sites: (i) at Fortress Mountain Powerline (2076 m ASL) and (ii) at Fortress Junction Service, located in a high elevation valley (1580 m ASL). On the western side, Nipika Mountain Resort, also located in a valley (1087 m ASL), was chosen as a field site. Various meteorological instruments were deployed including two Doppler LiDARs, three vertically pointing micro rain radars and three optical disdrometers. The three main sites were nearly identically instrumented, and observers were on site at Fortress Mountain Powerline and Nipika Mountain Resort during precipitation events to take manual observations of precipitation type and microphotographs of solid particles. The objective of the field campaign was to gather high temporal frequency meteorological data and to compare the different conditions on either side of the divide to study the precipitation processes that can lead to catastrophic flooding in the region. Details on field sites, instrumentation used, and collection methods are discussed. Data from the study are publicly accessible from the public Federated Research Data Repository (https://doi.org/10.20383/101.0221) (Thériault et al., 2020). This dataset will serve as a baseline for future work on atmospheric conditions over major orographic features by comparing the varying conditions on either side of a large topographic feature. This paper also provides a sample of the data gathered during a precipitation event.

For decades scholars have engaged in a lively debate about the distinctiveness of Canadian and American value systems. Lipset (1990) argues that divergent responses to the American Revolution led C...

The Ferruginous Hawk (Buteo regalis) is a keystone raptor in arid-land ecosystems in western North America that is experiencing population declines in some regions. Range-wide migration patterns, destinations, and chronology of adult hawks have not been described. Between 1999 and 2014, we captured 69 adult Ferruginous Hawks east and west of the Continental Divide and monitored them ≤6 yr with satellite telemetry to document their migration ecology. During a short time (x = 30 d, SD = 23) before migrating, 22% of hawks made brief movements away from territories (x = 211 km, SD = 133) and then returned. Migrating hawks (98% of 89 analyzed patterns) moved across broad fronts using five different strategies in three distinct periods: summer (July–August), fall (September–November), and spring (February–March). Breeding range longitude and latitude strongly influenced (r = 0.78) timing of summer migration that was directed to focal areas shared by breeding populations of hawks in the Northern Grasslands and Central Plains. Hawks nesting in grasslands from Canada to the Southern Plains demonstrated a strong pattern of southward migration to summer and winter ranges along the east front of the Rocky Mountains to central Mexico. Hawks from shrub-steppes in the Columbia Basin and Great Basin migrated eastward to summer ranges across the Continental Divide to grasslands, then to wintering areas in California and northern Mexico. On average, adult hawks spent 64% of the year away from breeding home ranges and migrated 2376 km (SD = 1165) annually, but differences in migration destinations, distance (P = 0.048), and duration (P < 0.0001) among populations potentially exposed them to variable levels and types of stressors. Accordingly, conservation of nonbreeding habitats used by Ferruginous Hawks is important for maintaining health of breeding populations; conservation efforts should emphasize protection of fossorial prey and habitats on shared summer ranges and winter ranges in the Mexican grasslands and Central Valley of California.

Background: Topoclimate can influence tree establishment within treeline ecotones. Yet much less is known about how regional topography, such as the Continental Divide, Rocky Mountains, mediates the role of climate in governing treeline dynamics.Aims: To utilise the Continental Divide to test whether contrasts in growing-season moisture regimes to the west (summer-dry) and east (summer-wet) impact the spatio-temporal patterns of tree establishment and rates of treeline advance in the Northern Rocky Mountains.Methods: We sampled trees at sites on north- and south-facing slopes, west and east of the Continental Divide. We used dendroecological techniques to reconstruct patterns of tree establishment. Age-structure data were quantitatively compared with climate to evaluate possible mechanistic linkages.Results: Across all sites, 96% of trees established after 1950. There was a treeline advance (range = 39–140 m) accompanied by increases in tree density. Significantly more trees established during wet...

Intracontinental endorheic basins are key elements of source-to-sink systems as they preserve sediments eroded from surrounding catchments. Drainage reorganization in such a basin has strong implications on the sediment routing system and on the landscape evolution at a cratonic scale. The Ebro and Duero basins in the north Iberian plate represent two foreland basins, which were filled in relation with the growing of surrounding compressional orogens as the Pyrenees and the Cantabrian mountains to the north, the Iberian and Central Ranges to the south, and the Catalan Coastal Range to the east. They were once connected as endorheic basins in the Early Oligocene. By the end of the Miocene, they were disconnected and started to flow into the Mediterranean Sea and the Atlantic Ocean, respectively, in a post-orogenic context. Although these two hydrographic basins recorded similar histories, they are characterized by very different morphologic features. The Ebro basin is highly excavated, whereas the Duero basin is well preserved and may be considered as almost still endorheic. These two bordering basins then show contrasting preservation states of their endorheic stages and represent an ideal natural laboratory to study what factors (internal / external) control drainage divide mobility, and drainage network and landscape evolution in post-orogenic basins. To that aim, we use field and map observations and we apply the Chi-analysis of river profiles across the divide along the boundary between the Ebro and Duero drainage basins in the Northern Iberian Peninsula to evaluate the migration of their divide. We show here that contrasting excavation of the Ebro and Duero basins drives a reorganization of their drainage network through a series of captures and resulted in the southwestward migration of their main drainage divide. Fluvial captures have strong impact on drainage areas, fluxes, and so on incision capacity, especially for the captured basin. Thus, we conclude that drainage reorganization, and capture of the Duero rivers by the Ebro ones, independently from tectonics and climate, enable endorheism in the Duero basin due to drainage area loss.

The recent discovery of a fossil of Enhydritherium terraenovae in upper Miocene fluvial deposits in Juchipila (Mexico), nearly 200 km away from the nearest coast, together with other known occurrences of the same species in Florida and California, made possible to envision an alternative to the Panamanian and Polar routes of migration through fluvial systems in Mexico. In order to cross from one ocean to the other, individuals of E. terraenovae must have passed the continental divide, which is a physiographic feature that separates surface waters that flow into the Atlantic and Pacific versants. Two vast endorheic regions, which together span more than 400,000 km2 in area, currently dominate drainage systems in northern and central Mexico. The endorheic regions are broadly bounded by two mountain ranges and coincide with the arid and semi-arid regions of the Chihuahuan desert. These closed basins are an additional obstacle for migration. However, drainage systems are constantly varying and adjusting to changing conditions imposed by climate, tectonic activity, volcanism, and pronounced asymmetries in topography and rainfall distribution. The migration route across Mexico for Enhydritherium terraenovae in the late Miocene (≥6 Ma) could have been facilitated by one or more river captures that inverted the flow direction near the headwaters of a drainage system that debouched either into the Gulf of Mexico or the Pacific coast. Biologists studying fresh water fish faunas in the southern part of the United States and in northern and central Mexico have documented several living species that occur in both the Rio Grande and in the Mezquital rivers, two drainages that are not presently connected, drain in opposite directions (i.e. towards the Gulf of Mexico and the Gulf of California, respectively) and are separated by the endorheic regions. Furthermore, systematic studies of fresh water fish faunas in the region has numerous examples of endemicity and allopatric speciations that are interpreted as evidence of several events of drainage system rearrangement either by stream capture, beheading, or river diversion or by fragmentation caused by formation of closed basins by faulting, volcanic activity or isostatic rebound in the footwall block of normal faults. The western boundaries of the extensive endorheic regions in Mexico are controlled mainly by a highland produced by intense felsic volcanism during the Sierra Madre Occidental activity (Eocene – Miocene), and the eastern hydrological divide coincides with mountains associated with the fold and thrust belt produced by the Hidalgoan orogeny in early Cenozoic time. Normal faulting associated with Basin and Range extension formed additional closed basins. Another major factor in the formation of the endorheic regions is the terminal Miocene climate change, which caused runoff reduction and lowered the rivers capacity of erosion. Opening of the Gulf of California changed the overall slope of rivers draining into the Pacific in northwestern Mexico triggering the capture of rivers formerly confined to the closed basins or draining to the Gulf of Mexico. Quaternary normal faults have been documented a few tens of kilometers from the hydrological divides of the endorheic regions, suggesting that in some regions there is an active tectonic component in their formation. The location of the crossing point for the otters is uncertain as the fossil record is scant and investigation on the evolution of drainage systems through time in Mexico is in the early stages. However, it is argued that there is a fair chance that the crossing occurred via the Mezquital river capture near Durango city. Isotopic age of the sediments where the Enhydritherium terraenovae fossil was collected, imply that the capture must have occurred in the late Miocene.

The kingpin structure of the American scheme to construct a ship canal across Panama in 1907–1914 was an earthen dam of unprecedented scale and scope at Gatun, to retain the aggregate flow of the Chagres River and its principal tributaries. Upon this structure alone, the entire plan rested, because it created the man-made lake rising 85 ft (25.9 m) above sea level, which allowed ships to cross the 550 ft (167.6 m) continental divide between the Atlantic and Pacific Oceans. Everything about Gatun Dam was enormous. Its dimensions were without precedent: a crest length of 8,200 ft (2,500 m) and a maximum width of 2,300 ft (701 m). With a height of 105 ft (32 m) above sea level, it stored sufficient water to maintain an operating pool covering 164 mi2 (425 km2). At its center was the most critical structure, a mass concrete spillway capable of passing flood flows of the unpredictable Chagres River. The biggest problem with the site was the underlying geology, which included two deepley incised paleo-channels. The massive embankments were placed over these paleo-channels, which were up to 258 ft (78.6 m) deep. The channel infill of the upper 50 ft (15.2 m) was of relatively low permeability, mostly sandy silts and clay. There were more pervious sands and gravel lying beneath these, which allowed deep seepage cutoffs to be precluded.

The Appalachian Trail (AT), Pacific Crest Trail (PCT), and Continental Divide Trail (CDT) are arguably the most popular long-distance hiking routes in the United States. With increasing need for recreational space, these trails are experiencing heavier visitation and impact. Research on the experiences of long-distance hikers can be used as a means of justifying funding for the management of the AT, PCT, CDT, and other long-distance trails. This study used the Benefits of Hiking Scale to determine whether benefits of participation and components of means-end theory varied based on the duration and location of long-distance hiking experiences. The study used an online survey to collect data from 292 hikers, who were classified as non-thru-hikers, AT thru-hikers, or thru-hikers of other long-distance trails. The number of thru-hikes completed in the last 10 years was also calculated. Results suggest that non-thru-hikers seek to maintain or improve physical health to a greater degree than thru-hikers, who appear to be motivated by other aspects of the hiking experience. Subscribe to JOREL

A new Cenozoic geologic and glacial history paradigm (new paradigm) describes massive and prolonged continental ice sheet meltwater floods that eroded the Colorado Royal Gorge area and surrounding regions and which were diverted in east, northeast, and even north directions as uplift of a thick ice sheet created deep “hole” rim gradually occurred (the thick ice sheet was located where North American ice sheets are usually recognized to have existed). A deep “hole” rim segment followed what is now the northern and central Colorado east-west continental divide southward to the Arkansas River headwaters area and then continued south along the Sangre de Cristo Mountains crestline to at least the Purgatoire River-Canadian River drainage divide and may have continued east from that point along a less well-defined zone beginning with what is now the Purgatoire River-Canadian River drainage divide. Diverging and converging valley complexes, barbed tributaries, and Arkansas River and other drainage route direction changes (easily seen on United States Geological Survey detailed topographic maps) are interpreted to have developed as the south-oriented floodwaters first flowed across the rising deep “hole” rim to reach the south- and southeast-oriented Rio Grande River drainage basin and were subsequently blocked by deep “hole” rim uplift and diverted to flow in east, northeast, and north directions. The accepted Cenozoic geologic and glacial history paradigm (accepted paradigm) has to date been unable to satisfactorily explain the detailed topographic map drainage system and erosional landform evidence and the new and accepted paradigms are incommensurable and lead to quite different Cenozoic geologic and glacial histories.

Understanding movement behavior and identifying areas of landscape connectivity is critical for the conservation of many species. However, collecting fine-scale movement data can be prohibitively time consuming and costly, especially for rare or endangered species, whereas existing data sets may provide the best available information on animal movement. Contemporary movement models may not be an option for modeling existing data due to low temporal resolution and large or unusual error structures, but inference can still be obtained using a functional movement modeling approach. We use a functional movement model to perform a population-level analysis of telemetry data collected during the reintroduction of Canada lynx to Colorado. Little is known about southern lynx populations compared to those in Canada and Alaska, and inference is often limited to a few individuals due to their low densities. Our analysis of a population of Canada lynx fills significant gaps in the knowledge of Canada lynx behavior at the southern edge of its historical range. We analyzed functions of individual-level movement paths, such as speed, residence time, and tortuosity, and identified a region of connectivity that extended north from the San Juan Mountains, along the continental divide, and terminated in Wyoming at the northern edge of the Southern Rocky Mountains. Individuals were able to traverse large distances across non-boreal habitat, including exploratory movements to the Greater Yellowstone area and beyond. We found evidence for an effect of seasonality and breeding status on many of the movement quantities and documented a potential reintroduction effect. Our findings provide the first analysis of Canada lynx movement in Colorado and substantially augment the information available for conservation and management decisions. The functional movement framework can be extended to other species and demonstrates that information on movement behavior can be obtained using existing data sets. This article is protected by copyright. All rights reserved.

The evolution of southwest Montana’s Big Hole and Beaverhead River drainage basins is determined from topographic map evidence related to mountain passes crossing what are today high altitude drainage divides including North America’s east-west Continental Divide. Map evidence, such as orientations of valleys leading away from mountain passes (and saddles) and barbed tributaries found along the downstream drainage routes, is used to reconstruct flow directions of streams and rivers that once crossed the present-day high mountain divides. Large south-oriented anastomosing complexes of diverging and converging channels are interpreted to have eroded what are today closely spaced passes and saddles now notched into high mountain ridges. Water in those south-oriented channels is interpreted to have flowed across emerging mountains and subsiding basins. Headward erosion of deeper southeast-oriented valleys, assisted by crustal warping, concentrated south-oriented water in fewer and deeper valleys as the water flowed from southwest Montana into what are today Idaho and the Snake River drainage basin. Headward erosion of the Big Hole River valley between the emerging Anaconda and Pioneer Mountains, also assisted by crustal warping, reversed all Big Hole Basin drainage so as to create the north-, east-, and south-oriented Big Hole River drainage route. A final and even more major reversal of flow in the present-day north-oriented Montana Missouri River valley, with the assistance of additional crustal warping, next ended all remaining flow to Idaho and the Snake River drainage basin and reversed and captured all drainage in the present-day north-oriented Big Hole, Beaverhead, and Red Rock River drainage basins. The observed map evidence indicates that prior to the final flow reversal events, large volumes of south-oriented water flowed across southwest Montana’s Big Hole and Beaverhead River drainage basins.

We report a comprehensive inventory of Be-10-based basin-wide denudation rates (n=160) and Al-26/Be-10 ratios (n=67) from 48 drainage basins along a 3,000 km stretch of the East Australian passive continental margin. We provide data from both basins draining east of the continental divide (n=37) and discharging into the Tasman and Coral Seas, and from basins draining to the west as part of the larger Murray-Darling and Lake Eyre river systems (n=11). Be-10-derived denudation rates in mainstem samples from east-draining basins range between 7.7 ± 1.9 (±1 sigma; Mary) and 54.6 ± 13.7 mm kyr-1 (North Johnstone). Denudation rates in tributary samples range between 3.0 ± 0.7 (Burdekin) and 70.2 ± 18.9 mm kyr-1 (Liverpool). For west-draining basins, denudation rates are overall lower and with a more restricted range of 4.8 ± 1.2 (Barcoo) to 15.4 ± 3.6 mm kyr-1 (Maranoa) in mainstem samples, and between 4.4 ± 1.0 (Murrumbidgee) and 38.5 ± 7.8 mm kyr-1 (Murray) in tributary samples. East Australian denudation rates (median all = 14.5 mm kyr-1; median east of continental divide = 15.9 mm kyr-1; median west of the continental divide = 9.3 mm kyr-1) are similar to those found in other postorogenic landscapes (global median = 12.4 mm kyr-1) and the medians of the top 10% denudation rates recorded here (46.5 mm kyr-1) and in other passive margin settings are also similar, despite differences in topography and precipitation. These median denudation rate values are close to the 95th percentile denudation rate for all tectonically passive basins (≈53 mm kyr-1) and are very similar to the global silicate weathering speed limit (≈58 mm kyr-1) calculated as the 95th percentile of global soil weathering rates. The above suggests that in post-orogenic terrain, the overall rates of topographic decay have a ‘speed limit’ that is imposed by the rate at which rock is converted to soil by chemical weathering. Denudation rates along the East Australian margin correlate with topographic metrics at both the mainstem basin scale and at the smaller tributary basin scale suggesting that topography exerts the main control on rates of landscape lowering in this setting. An important link between denudation rate and rainfall is also inferred: the highest mainstem Be-10 denudation rates all occur in basins which also have the highest rainfall amounts and there is a strong correlation between the distance knickpoints have travelled upstream from the river mouth and basin area — a proxy for discharge and so to some extent also rainfall. Lastly, we assign basin Al-26/Be-10 ratios to identify non-steady state sediment storage and generation processes. On both sides of the divide, in all but a few of the samples, Al-26/Be-10 ratios are consistently lower than what is expected in a setting where sediments experience a simple and continuous exposure history. East of the continental divide Al-26/Be-10 ratios range between 4.99 ± 0.31 (±1 sigma; Mitchell) and 7.86 ± 0.77 (Don), and between 3.96 ± 0.32 (Barcoo) and 6.39 ± 0.40 (Maranoa), west of the continental divide. East of the continental divide, the lowest Al-26/Be-10 ratios are found in basins that also experience increased flood variability. We posit that there is a causal link between the hydrological variability that characterises the coastal rivers of eastern Australia and the observed non-steady state Al-26/Be-10 ratios: the periodic stripping of vertically accreted floodplains by large floods means that deeper and potentially older material is periodically incorporated into the sediment mix transported by the modern river.

The United States Supreme Court settled legal disputes concerning four different Larimer County (Colorado) locations where water is moved by gravity across the high elevation North Platte-South Platte River drainage divide, which begins as a triple drainage divide with the Colorado River at Thunder Mountain (on the east-west continental divide and near Colorado River headwaters) and proceeds in roughly a north and northeast direction across deep mountain passes and other low points (divide crossings) first as the Michigan River (in the North Platte watershed)-Cache la Poudre River (in the South Platte watershed) drainage divide and then as the Laramie River (in the North Platte watershed)-Cache la Poudre River drainage divide. The mountain passes and nearby valley and drainage route orientations and other unusual erosional features can be explained if enormous and prolonged volumes of south-oriented water moved along today’s north-oriented North Platte and Laramie River alignments into what must have been a rising mountain region to reach south-oriented Colorado River headwaters. Mountain uplift in time forced a flow reversal in the Laramie River valley while flow continued in a south direction along the North Platte River alignment only to be forced to flow around the Medicine Bow Mountains south end and then to flow northward in the Laramie River valley and later to be captured by headward erosion of the east-oriented Cache la Poudre River-Joe Wright Creek valley (aided by a steeper gradient and less resistant bedrock). Continued uplift next reversed flow on the North Platte River alignment to create drainage routes seen today. While explaining Larimer County North Platte-South Platte drainage divide area topographic map drainage system and erosional landform evidence this interpretation requires a completely different Cenozoic history than the geologic history geologists usually describe.

Amongst the many challenges faced by society, climate change is one of the critical issues. This article aims to review the literature on voluntary employee green behaviour (VEGB) to identify and evaluate the contextual dispersion, the methodological variations, and the theoretical rigorousness of VEGB studies. A review of 65 research papers on VEGB shows a continental divide and prominence of quantitative research methodology over qualitative methodology. Further, though the researchers have used multi-level conceptual frameworks, only a handful of studies have applied multi-level analysis. Notably, the multi-theory applications in VEGB studies are rare. The study findings imply the need for uncovering the VEGB knowledge in developing country contexts, using multi-level analysis, and employing a multi-theory perspective to generate further knowledge about VEGB, which will be beneficial in mitigating eco-system damages and promoting a responsible society.