This paper describes the development of an android-based smartphone application aimed at capturing automatically triggered aerial photographs for grass-roots mapping applications. The aim of the project was to exploit the plethora of on-board sensors within modern smartphones (accelerometer, GPS, compass, camera) to generate ready-to-use spatial data from lightweight aerial platforms such as drones or kites. A visual coding 'scheme blocks' framework was used to build the application ('app'), so that users could customise their own data capture tools in the field. The paper reports on the coding framework, then shows the results of test flights from kites and
lightweight drones and finally shows how open-source geospatial toolkits were used to generate geographical information system (GIS)-ready GeoTIFF images from the metadata stored by the app. Two Android smartphones were used in testing - a high specification OnePlus One handset and a lower cost Acer Liquid Z3 handset, to test
the operational limits of the app on phones with different sensor sets. We demonstrate that best results were obtained when the phone was attached to a stable single line kite or to a gliding drone. Results show that engine or motor vibrations from powered aircraft required dampening to ensure capture of high quality images. We demonstrate
how the products generated from the open-source processing workflow are easily used in GIS. The app can be downloaded freely from the Google store by searching for 'UAV toolkit' (UAV toolkit 2016), and used wherever an Android smartphone and aerial platform are available to deliver rapid spatial data (e.g. in supporting decision-making in humanitarian disaster-relief zones, in teaching or for grassroots remote sensing and democratic mapping).

Northern Europe can be strongly influenced by winter storms driven by the North Atlantic
Oscillation (NAO), with a positive NAO index associated with greater storminess in northern
Europe. However, palaeoclimate reconstructions have suggested that the NAO-storminess
relationship observed during the instrumental period is not consistent with the relationship
over the last millennium, especially during the Little Ice Age (LIA), when it has been
suggested that enhanced storminess occurred during a phase of persistent negative NAO.
To assess this relationship over a longer time period, a storminess reconstruction from an
NAO-sensitive area (the Outer Hebrides) is compared with Late Holocene NAO
reconstructions. The patterns of storminess are inferred from aeolian sand deposits within
two ombrotrophic peat bogs, with multiple cores and two locations used to distinguish the
storminess signal from intra-site variability and local factors. The results suggest storminess
increased after 1000 cal yrs BP, with higher storminess during the Medieval Climate
Anomaly (MCA) than the LIA, supporting the hypothesis that the NAO-storminess
relationship was consistent with the instrumental period. However the shift from a
predominantly negative to positive NAO at c.2000 cal yrs BP preceded the increased
storminess by 1000 years. We suggest that the long-term trends in storminess were caused
by insolation changes, while oceanic forcing may have influenced millennial variability.

Abstract. Despite recent research identifying a clear anthropogenic impact on glacier recession, the effect of recent climate change on glacier-related hazards is at present unclear. Here we present the first global spatio-temporal assessment of glacial lake outburst floods (GLOFs) focusing explicitly on lake drainage following moraine dam failure. These floods occur as mountain glaciers recede and downwaste and many have an enormous impact on downstream communities and infrastructure. Our assessment of GLOFs associated with the collapse of moraine-dammed lakes provides insights into the historical trends of GLOFs and their distributions under current and future global climate change. We observe a clear global increase in GLOF frequency and their regularity around 1930, which likely represents a lagged response to post-Little Ice Age warming. Notably, we also show that GLOF frequency and their regularity – rather unexpectedly – has declined in recent decades even during a time of rapid glacier recession. Although previous studies have suggested that GLOFs will increase in response to climate warming and glacier recession, our global results demonstrate that this has not yet clearly happened. From assessment of the timing of climate forcing, lag times in glacier recession, lake formation and moraine dam failure, we predict increased GLOF frequencies during the next decades and into the 22nd century.
.

Micro x-ray fluorescence (µXRF) core scanning is capable of measuring the elemental composition of lake sediment at sub-millimetre resolution, but bioturbation and physical mixing may degrade environmental signals at such fine scales. The aim of this research is to determine the maximum possible resolution at which meaningful environmental signals may be reconstructed from lake sediments using this method. Sediment from a coastal lake in the Outer Hebrides, Scotland, has been analysed using calibrated element measurements to reconstruct storminess since AD 200. We find that a Ca/K ratio in lake-core sediments reflects the presence of fine calcium carbonate shell fragments, a constituent of sand in the catchment that is washed and blown into the lake. Variations in this ratio are significantly correlated with instrumental records of precipitation and low pressures, suggesting it is a proxy for storminess. Furthermore, identification of a c. 60-year cycle supports a climatic influence on Ca/K, as this cycle is frequently identified in reconstructions of the North Atlantic Oscillation and North Atlantic sea-surface temperature. Comparison with weather records at different resolutions and spectral analysis indicate that µXRF data from Loch Hosta can be interpreted at sub-decadal resolutions (equivalent to core depth intervals of 3–5 mm in this location). Therefore, we suggest that sub-centimetre sampling using µXRF core scanning could be beneficial in producing environmental reconstructions in many lake settings where sediments are not varved.

Understanding how landscapes respond to climate dynamics in terms of macroscale (average topographic features) and microscale (landform reorganization) is of interest both for deciphering past climates from today's landscapes and for predicting future landscapes in view of recent climatic trends. Although several studies have addressed macro-scale response, only a few have focused on quantifying smaller-scale basin reorganization. To that goal, a series of controlled laboratory experiments were conducted where a self-organized complete drainage network emerged under constant precipitation and uplift dynamics. Once steady state was achieved, the landscape was subjected to a fivefold increase in precipitation (transient state). Throughout the evolution, high-resolution spatiotemporal topographic data in the form of digital elevation models were collected. The steady state landscape was shown to possess three distinct geomorphic regimes (unchannelized hillslopes, debris-dominated channels, and fluvially dominated channels). During transient state, landscape reorganization was observed to be driven by hillslopes via accelerated erosion, ridge lowering, channel widening, and reduction of basin relief as opposed to channel base-level reduction. Quantitative metrics on which these conclusions were based included slope-area curve, correlation analysis of spatial and temporal elevation increments, and wavelet spectral analysis of the evolving landscapes. Our results highlight that landscape reorganization in response to increased precipitation seems to follow "an arrow of scale": major elevation change initiates at the hillslope scale driving erosional regime change at intermediate scales and further cascading to geomorphic changes at the channel scale as time evolves. Key Points: Climate shifts reorganize landscapes at all scales Fluvial regime expands to smaller scales under increased precipitation Landscape reorganization mainly driven by hillslope erosion

Landslides present a geomorphological hazard in Alpine regions, threatening life, infrastructure and property. Here we present the development of a new regional landslide inventory (RI) for the European Alps. This database provides a substantial temporal and spatial picture of landsliding in the Alps, with particular focus on the Swiss and French Alps. We use segmented models to evaluate recording bias in the temporal record. We use scaling relationships to calculate landslide area based on a given volume for similar types of landslide; with the result of this being that 9.5% of the landslides recorded in the RI now have area data recorded. These landslide area data are then used to examine the log-linear trend, which exists between landslide area and frequency in inventories. We show that this relationship is present for this historical dataset; however, none of the individual databases, nor a unification of these, contain a complete record with the small and larger landslides being recorded more consistently. The use of segmented models on the temporal distribution of landslides in the RI shows that the post-1970 portion of the database is more reliable, highlighted through an improved power-law relationship, although the frequency of medium sized landslides is still underestimated. We show that creating a unified database (RI) can increase the reliability of datasets and consistency in recording for the use by researchers for attribution and detection studies.

We conducted a series of four physical modeling experiments of mountain growth at differing rates of uplift and three distinct climates ranging from relatively wet to relatively dry. The spatial and temporal pattern of landscape behavior is characterized by f-1 scaling in sediment discharge and power law scaling in the magnitude and frequency of ridge movement in all four experiments. We find that internally generated self-organized critical (SOC) processes generate dynamically stable catchment geometries after 1 relief depths of erosion: these regularly spaced catchments have an average outlet-spacing ratio of 2.16, well within the range of values reported in field studies. Once formed, large catchment bounding ridges oscillate about a critically balanced mean location, with occasional large-scale changes in catchment size. Ridge movement appears to be driven by the competition for discharge as landslides push ridges back and forth. These dynamics lead to the emergence of a complex twofold scaling in catchment dynamics that is fully established by 1.8 relief depths of erosion; at this stage, a clear threshold has emerged separating two distinct scaling regimes, where large ridge mobility is insensitive to relief and small ridge mobility is relief dependent. Overall, we demonstrate that the development of dynamically stable large-scale landforms is related to the emergence of a complex-system hierarchy in topographic dynamics. Once formed, these landscapes do not evolve; statistical properties such as average topography and discharge become stationary while topography remains highly dynamic at smaller length scales.

Historical and documentary records from the Petit Lac d'Annecy, indicate that human activities have been the dominant 'geomorphic process' shaping the catchment during the late Holocene, with deforestation, agriculture and artificial drainage profoundly affecting both the pace and spatial distribution of soil erosion. The impact of past climatic change on the evolution of the catchment is less certain because of the lack of long-term climate records for the site. Previous attempts to use the sediment record from the lake to investigate the role past climate change may have played were hampered by the difficulty in isolating and disentangling the climatic signal preserved within the archive, because of overprinting of human activity. This is a common problem in regions with a long history of human activity in the landscape. In this study we use a range of novel statistical techniques (including cross-correlation and cross spectral analysis) to assess the relative importance of climate in driving landscape dynamics. The statistical analysis is carried out on an updated high-resolution palaeo-environmental data set from the Petit Lac d'Annecy. The results of the statistical analysis indicate that regional climate phenomena such as the Atlantic multidecadal oscillation are partly responsible for landscape dynamics at Petit Lac d'Annecy throughout the late Holocene. We find that the Petit Lac d'Annecy catchment typically requires decades, or longer, to respond to changes in precipitation, reflecting the stochastic nature of river sediment storage and transport. The use of a 4 yr integrated lake core record effectively attenuates the 'signal shredding' effect of shorter-term internally generated sediment transport processes. Nonetheless, the lake record of climatically induced geormorphic process-responses is weak compared with the pervasive impact of human activities. © the Author(s) 2013.

There appears to be no single axis of causality between life and its landscape, but rather, each exerts a simultaneous influence on the other over a wide range of temporal and spatial scales. This view conflicts with the long-standing paradigm that physical processes sculpt a landscape and set the template on which biological agents occur. Failure to incorporate the dynamic interactions among human activity, biota and surface processes in landscape studies limits our ability to predict the response of landscapes to human disturbance and climate change. This limitation is a direct result of the poor communication between the ecological and geomorphological communities and consequent paucity of interdisciplinary research. Recognition of this failure led to the organization of the Meeting of Young Researchers in Earth Science (MYRES) III, titled “Dynamic Interactions of Life and its Landscape”. This paper synthesizes and expands upon key issues and findings from that meeting, to help chart a course for future collaboration among Earth surface scientists and ecologists: it represents the consensus view of a select group of 77 early-career researchers. We identify two broad themes that serve to focus and motivate future research: (1) Co-evolution of landforms and biological communities; and (2) Humans as modifiers of the landscape (through direct and indirect actions). We also outline the state of the art in analytical, experimental and modeling techniques in ecological and geomorphological research, and suggest novel new research avenues that combine these techniques. It is our hope that this paper will serve as an interdisciplinary reference for geomorphologists and ecologists looking to learn more about the other field.

The following is a white paper (adapted here for print) for the U.S. National Research Council's committee on
Challenges and Opportunities in Earth Surface Processes, drafted at a National Science Foundation sponsored
workshop associated with the 38th Binghamton Geomorphology Symposium, “Complexity in Geomorphology,”
held at Duke University in October 2007.

Rapid growth of quantitative analysis and prediction in Earth-surface science has been
accompanied by rapid growth in experimental stratigraphy and geomorphology.
Experimenters have grown increasingly bold in targeting landscape elements like channel
reaches, erosional networks, and whole depositional basins, often using very small
facilities. These experiments produce spatial structure and kinematics that compare well
with natural systems despite extreme differences of spatial scale, time scale, material
properties, and number of active processes. Experiments have been particularly useful in
discovering and analyzing the many types of self-organized (autogenic) complexity that
occur in morphodynamic systems. Autogenic dynamics creates many of the spatial
patterns we see in the landscape and preserved strata. Dynamically it is strongly
associated with sediment storage and release.
Similarity between experimental and field systems occurs despite large differences in
governing dimensionless numbers, whence the term “unreasonable effectiveness”. We
suggest that the explanation of unreasonable experimental effectiveness arises from
natural scale independence. We generalize existing ideas to relate internal similarity, in
which a small part of a system is similar to the larger system, to external similarity, in
which a small copy of a system is similar to the larger system. We suggest that internal
similarity implies external similarity, though not the converse. The external similarity of
landscape experiments to natural landscapes suggests that natural scale independence
may be even more characteristic of morphodynamics than it is of better studied cases
such as turbulence. We urge a shift in emphasis in experimental stratigraphy and
geomorphology away from dynamical scaling and towards a quantitative understanding
of the origins and limits of scale independence. Other research areas with strong growth
potential include physical-biotic interactions, cohesive effects, stochastic processes,
interaction of structural and geomorphic self-organization, recording and interpretation of
external forcing, and quantitative model testing.

We integrated optically stimulated luminescence dating and 10Be cosmogenic
nuclide measurements to quantify short-to-medium-term (102–104 years) catchment
dynamics and response to active tectonics. In the 27 km2 Rı´o Torrente catchment, Sierra
Nevada, southern Spain, rapid base-level fall has triggered knickpoint migration up
both trunk and tributary channels, resulting in two distinct geomorphic zones: (1) a steep
lower catchment with concordant rates of hillslope erosion and channel incision over
both short (100 years: 5–8 mm yr 1) and medium (12 ka: 5 ± 1 mm yr 1) timescales and
(2) a low-relief soil-mantled upland topography with uniformly low bedrock and hillslope
erosion rates (0.05 ± 0.02 mm yr 1). The uniformity of erosion in this upland surface
indicates that catchment topography was previously in steady state. Rapid river incision
below the channel knickpoints has resulted in the development of steep landslidedominated
hillslopes that are essentially ‘‘tracking’’ the incising channel. The magnitude
of base-level fall required to generate these steep hillslopes is >100 m; at least 50 m
of this base-level fall occurred during the past. 21 ka. These steep hillslopes are eroding
back into the low-angled upland surface at a much slower rate than the channel knickpoint.
Consequently, the trunk channel knickpoint has already reached the catchment headwaters
while hillslopes continue to adjust to the new base level, indicating that the channel
profile will regain equilibrium form long before hillslopes. Thus hillslopes are the limiting
factor for the duration of landscape transience in this small mountain catchment.

The denudation history of the rapidly uplifting
western part of the Spanish Sierra Nevada was
assessed using apatite fission track (AFT) ages and 10Be analyses of bedrock and fluvial sediments. Major contrasts in the denudation history are recorded within
the 27 km2 Rı´o Torrente catchment. Upland areas are
characterized by low-relief, low slope angles, and
locally the preservation of shallow marine sediments,
which have experienced 2 km of denudation since circa 4 Ma. The
minimum denudation rates of 0.4 mm yr 1 derived
from AFT also contrast with the slow medium-term
(104 years) erosion rates (0.044 ± 0.015 mm yr 1)
estimated from 10Be measurements at high elevations.
The local medium-long-term contrasts in denudation
rates within the high Sierra Nevada indicate that much
of the unroofing occurs by tectonic denudation on flatlying
detachments. In lower elevation parts of the
catchment, rapid river incision coupled to rock uplift
has produced. 1.6 km of relief, implying that the
rivers and adjacent hillslopes close to the edge of the
orogen are sensitive to normal-fault-driven changes in
base level. However, these changes are not transmitted
into the low-relief slowly eroding upland areas. Thus
the core of the mountain range continues to increase in
elevation until the limits of crustal strength are reached
and denudation is initiated along planes of structural
weakness. We propose that this form of tectonic
denudation provides an effective limit to relief in young orogens.