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In March and April 2021, buoys were deployed in the Beaufort Sea, Arctic Ocean, to measure sea‐ice horizontal deformation over spatial scales that had not been previously achieved. Geodetic‐quality position measurements allowed measurements of strain‐rate over lengths from about 200 m to 2 km. Conventional ice‐drifters extended spatial coverage up to about 100 km. Past studies find there is multi‐fractal behavior for horizontal sea‐ice deformation from 10 to 1,000 km. Our results demonstrate that such behavior does not hold when including spatial scales below 10 km. We find that sea‐ice deformation is not scale invariant between the scale of individual sea‐ice floes and aggregates of floes. Therefore, we cannot expect the same physical laws or forcing to describe sea‐ice kinematics over these regimes, nor can we assume log‐log linear behavior for mean deformation. Using this scaling behavior as a metric to validate models that resolve sea ice floes and their interactions is hence not recommended. In March and April of 2021, a nested array of buoys was deployed around a drifting camp on sea ice 50 km off‐shore in the Beaufort Sea, Arctic Ocean. The inner buoys of the array measured their position with centimeter‐level accuracy allowing for measurements of sea ice deformation at a wide range of spatial scales. Sea ice deformation includes the opening and closing of the ice and shearing motion that occurs along cracks in the ice known as leads and ridges. This experiment was the first time that sea‐ice deformation has been analyzed over scales from 100s of meters to 100s of kilometers. Past studies over areas spanning more than 10 km suggest that the sea‐ice deformation has fractal behavior, a mathematical relationship where the rates of deformation increase as you measure over increasingly smaller regions. Past measurements of deformation over smaller areas found a different fractal behavior. In this study, we find that the mathematical relationship does not fit observations across any region larger than a kilometer square. We conclude that sea‐ice deformation is not fractal and caution against assuming that this relationship exists for climate and forecast modeling. Results from the first field experiment measuring sea‐ice deformation across spatial scales ranging from 200 m to over 100 km are presentedPrevious studies indicate sea‐ice deformation is multi‐fractal for scales above 10 km, and we find this does not holdOver spatial scales from 1 to ∼100 km, deformation does not scale log‐log linearly with separation distance, and is not fractal Results from the first field experiment measuring sea‐ice deformation across spatial scales ranging from 200 m to over 100 km are presented Previous studies indicate sea‐ice deformation is multi‐fractal for scales above 10 km, and we find this does not hold Over spatial scales from 1 to ∼100 km, deformation does not scale log‐log linearly with separation distance, and is not fractal

We study a mechanism of iceberg breakup that may act together with the recognized melt and wave‐induced decay processes. Our proposal is based on observations from a recent field experiment on a large ice island in Baffin Bay, East Canada. We observed that successive collapses of the overburden from above an unsupported wavecut at the iceberg waterline created a submerged foot fringing the berg. The buoyancy stresses induced by such a foot may be sufficient to cause moderate‐sized bergs to break off from the main berg. A mathematical model is developed to test the feasibility of this mechanism. The results suggest that once the foot reaches a critical length, the induced stresses are sufficient to cause calving. The theoretically predicted maximum stable foot length compares well to the data collected in situ. Further, the model provides analytical expressions for the previously observed “rampart‐moat” iceberg surface profiles. Observational iceberg data from 2012 Baffin Bay field experimentMathematical model of iceberg decay due to hydrostatic stressesAnalytic expressions for iceberg profiles and breakup conditions developed

Increasing freshwater input to the subpolar North Atlantic through iceberg melting can influence fjord‐scale to basin‐scale ocean circulation. However, the magnitude, timing, and distribution of this freshwater have been challenging to quantify due to minimal direct observations of subsurface iceberg geometry and melt rates. Here we present novel in situ methods capturing iceberg change at high‐temporal and ‐spatial resolution using four high‐precision GPS units deployed on two large icebergs (>500 m length). In combination with measurements of surface and subsurface geometry, we calculate iceberg melt rates between 0.10 and 0.27 m/d over the 9‐day survey. These melt rates are lower than those proposed in previous studies, likely due to using individual subsurface iceberg geometries in calculations. In combining these new measurements of iceberg geometry and melt rate with the broad spatial coverage of remote sensing, we can better predict the impact of increasing freshwater injection from the Greenland Ice Sheet. The acceleration of Greenland glaciers has led to an increase of icebergs discharged in nearby waters. As icebergs melt, they release freshwater into salty ocean waters, impacting local circulation. In order to understand how global circulation will change in the future, we need accurate iceberg melt rates. To do this, we use measurements of mass loss from on‐iceberg GPS units, and three‐dimensional iceberg geometry constructed from aerial drone and subsurface sonar data. We found melt rates smaller than previous studies and strong evidence for variable overall melt rates with different keel depths and over time. This study is the first of its kind to calculate melt rates using exact iceberg geometry. To better predict iceberg impacts, future iceberg studies should take these geometry results into account. High resolution on‐iceberg GPS units show temporally variable melt rate over the 9‐day survey periodContrasting melt rates between different sized icebergs supports the hypothesis of depth‐variable melt ratesMelt rates are lower than prior studies, likely due to using observed subsurface geometry (not idealized or end‐member) in calculations High resolution on‐iceberg GPS units show temporally variable melt rate over the 9‐day survey period Contrasting melt rates between different sized icebergs supports the hypothesis of depth‐variable melt rates Melt rates are lower than prior studies, likely due to using observed subsurface geometry (not idealized or end‐member) in calculations

This paper empirically investigates how economic activity in Argentina at regional and provincial (i.e., state) levels responds to central national monetary policy shocks, as given by a change in the interest rate. Regional heterogeneity of monetary shocks exists in Argentina. At the regional level the long-term effects of increasing the interest rate are negative and statistically significant. At the provincial level, 11 provinces show a negative and significant impact of a shock on the interest rate over employment. However, there are 13 provinces in which the effect is not statistically significant, including the City of Buenos Aires and Buenos Aires Province. Bayesian methods are implemented to study the discrepancies in the impact on different provinces.