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This paper introduces a comprehensive protocol leveraging open-access techniques to create small- to medium-scale 3D representations of the environment by using iPhone and iPad light detection and ranging (LiDAR). The protocol focuses on two capabilities of the iPhone LiDAR. The first capability is 3D modeling: iPhone LiDAR rapidly generates detailed indoor and outdoor 3D models, providing insights into object size, volume and geometry. The second capability is change detection: the 3D models created by the LiDAR sensor can be used for precise measurement of changes over time. Compared to other 3D topographic surveying methods, this method is rapid, high resolution, low cost and easy to use. The protocol outlines iPhone LiDAR scanning practices, model export and change detection. The expected results after executing the protocol are (i) a detailed 3D model of a small- to medium-sized object or area of interest and (ii) a distance point cloud revealing change between two point clouds of the same object or area between different times. The entire protocol can be conducted within 2 h by anyone with an iPhone with the LiDAR sensor and a computer. This protocol empowers scientists, students and community members conducting research with a cheap, easy-to-use method for addressing a range of questions and challenges, thus benefiting experts and the broader community.

Groundwater springs in permafrost regions provide pathways for solutes and dissolved gases to escape from sub‐permafrost groundwater systems, which otherwise are completely isolated from the surface environment and atmosphere. Yet, fundamental questions as to the mechanisms driving groundwater flow to the surface remain unsolved. In this study, basal permafrost aggradation is explored as a mechanism for generating groundwater flow and driving groundwater spring systems. We employ process‐based numerical modeling to test the hypothesis of permafrost‐aggradation‐driven spring systems in a range of environmental settings. The model results show that permafrost aggradation can generate spring flow on a multi‐millennial timescale and with discharge rates up to a couple of liters per second. Permafrost aggradation deserves attention as a groundwater flow driving mechanism in areas of recent glacio‐isostatic uplift and glacial retreat. In the High Arctic, the subsurface is frozen in a state called permafrost. Since fluids cannot flow through ice, surface water only flows close to the surface, while groundwater below the permafrost is trapped—sometimes along with large amounts of greenhouse gases. In some permafrost locations, groundwater springs allow groundwater to reach the surface and atmosphere from the deep subsurface. Unlike non‐permafrost regions, these locations often lack routes for surface water to flow beneath the permafrost, which means that the spring outflow is not balanced by incoming water. In this study, we investigate the idea that when permafrost grows deeper, the expansion of groundwater as it freezes creates enough pressure to cause the spring outflow. We use a computer model to simulate this process, and our results show that permafrost growth can generate spring outflow for millennia, reaching a flow rate of a few liters per second. This new understanding is crucial for predicting how greenhouse gas emissions from groundwater springs in permafrost will respond to climate change. It is also relevant for the long‐term deposition of hazardous materials, such as nuclear waste, as it provides a mechanism for contaminants to spread from the deep subsurface to surface systems. Hydraulic pressure generation from millennial‐scale permafrost aggradation is investigated as a new mechanism for driving groundwater flowFreezing pressure induced at the base of aggrading permafrost can drive Arctic spring systems for millenniaThis mechanism deserves attention in areas of recent glacio‐isostatic uplift and glacial retreat Hydraulic pressure generation from millennial‐scale permafrost aggradation is investigated as a new mechanism for driving groundwater flow Freezing pressure induced at the base of aggrading permafrost can drive Arctic spring systems for millennia This mechanism deserves attention in areas of recent glacio‐isostatic uplift and glacial retreat

Climate changes are pronounced in Arctic regions and increase the vulnerability of the Arctic coastal zone. For example, increases in melting of the Greenland Ice Sheet and reductions in sea ice and permafrost distribution are likely to alter coastal morphodynamics. The deltas of Greenland are largely unaffected by human activity, but increased freshwater runoff and sediment fluxes may increase the size of the deltas, whereas increased wave activity in ice-free periods could reduce their size, with the net impact being unclear until now. Here we show that southwestern Greenland deltas were largely stable from the 1940s to 1980s, but prograded (that is, sediment deposition extended the delta into the sea) in a warming Arctic from the 1980s to 2010s. Our results are based on the areal changes of 121 deltas since the 1940s, assessed using newly discovered aerial photographs and remotely sensed imagery. We find that delta progradation was driven by high freshwater runoff from the Greenland Ice Sheet coinciding with periods of open water. Progradation was controlled by the local initial environmental conditions (that is, accumulated air temperatures above 0 °C per year, freshwater runoff and sea ice in the 1980s) rather than by local changes in these conditions from the 1980s to 2010s at each delta. This is in contrast to a dominantly eroding trend of Arctic sedimentary coasts along the coastal plains of Alaska, Siberia and western Canada, and to the spatially variable patterns of erosion and accretion along the large deltas of the main rivers in the Arctic. Our results improve the understanding of Arctic coastal evolution in a changing climate, and reveal the impacts on coastal areas of increasing ice mass loss and the associated freshwater runoff and lengthening of open-water periods.

Geografisk Tidsskrift—Danish Journal of Geography 110(2):357–363, 2010Geografisk Tidsskrift—Danish Journal of Geography 110(2):365–371, 2010

AbstractGeografisk Tidsskrift—Danish Journal of Geography 110(2):131–142, 2010One of the most prominent polynyas in Northeast Greenland, already noted by the early expeditions in the area, is located around Shannon Ø and Pendulum Øer between 75° and 74°N in the transition zone between the fast ice and pack ice. This study names the polynya the ‘Sirius Water Polynya’, and examines its spatial and temporal dynamics by analysis of recent satellite imagery, modelled meteorological data and historical data covering the last decade. The dominating mechanisms to form and sustain the polynya are inferred and the persistence and inter-annual variability of the phenomenon are estimated. The polynya formation is predominantly governed by mechanical forcing caused by northerly gales, and it is classified as a wind-driven shelf water polynya. A marked seasonal difference in the surface wind field, together with the obvious seasonal cycle in insolation, creates distinct winter and summer regimes in the seasonal evolution of the polynya. During the winter regime, both the size of and the ice cover within the polynya varies significantly on a temporal and spatial scale. Intermittent wind-driven openings of the polynya alternate with periods of increasing ice cover. Some of the most persistent areas of open water in the polynya coincide with locations where significant concentrations of spring and summer settlements from the Thule Inuit culture (AD 1400–1850) are observed, indicating a connection between the presence of the polynya and the Thule Inuit living in the area in prehistoric times.

AbstractGeografisk Tidsskrift—Danish Journal of Geography 110(2):143–154, 2010Inuit have travelled to and settled in the coastal landscapes of Northeast Greenland for several longer periods during the latest ca. 4500 years. Most recently the Thule culture Inuit lived in the region from around 1400 until 1850 AD. The access to partly and periodically ice covered near coastal waters has been crucial to the primarily marine based subsistence strategy of the Thule Inuit culture, and their settlements are therefore found immediately at the coast. Changing geological and geomorphologic settings strongly influence the coastal morphodynamics, and only specific locations offer stable and protected conditions needed for proper winter settlements. The comprehensive study of coastal environments and Thule culture winter settlements in the Young Sound region show an accumulation of winter settlements, nearly all located either in protected pocket beaches or on stable basalt capes. The Thule culture abandoned Northeast Greenland about 1850 AD, and apart from settlements on basalt capes, most of the winter settlement sites in pocket beach areas have been affected by erosion of local character and in some cases also affected by increasing wave erosion during recent periods of less ice in near coastal waters.