Rapid and, in many cases, unprecedented Arctic climate changes are having far-reaching impacts on natural and human systems. Despite state-of-the-art models capturing the rapid nature of change, termed amplification, they significantly disagree its magnitude. Using a regional, process-oriented surface energy budget analysis, we argue that differences seasonal exchanges sea ice retreat regions via increased absorption storage sunlight summer upward turbulent fluxes fall/winter contribute to...

Abstract Radiative energy fluxes exiting the atmosphere toward surface and to space are sensitive vertical structure of temperature. Under anthropogenic forcing, this sensitivity gives rise lapse‐rate feedback. Negative in tropics positive Arctic, studies argue that feedback is a primary cause Arctic Amplification. While negative tropical understood mechanistically, mechanics less clear. Stable stratification necessary condition for feedback; however, does stable place any further constraint...

Abstract The Arctic region is warming at a rate more than double the global average, trend predicted to continue by all Coupled Model Intercomparison Project 5 (CMIP5) climate models. Despite this consistency, significant intermodel spread exists in simulated related differences surface radiation budget. Building upon previous work characterize and understand budget biases models, annual mean seasonal cycle of 17 CMIP5 models using Historical‐forcing scenario evaluated against...

Abstract. Arctic clouds exhibit a robust annual cycle with maximum cloudiness in fall and minimum winter. These variations affect energy flows the large influence on surface radiative fluxes. Contemporary climate models struggle to reproduce observed cloud amount significantly disagree each other. The goal of this analysis is quantify cloud-influencing factors that contribute winter–summer differences, as these seasons are primarily responsible for model discrepancies observations. We find...

Abstract A modified automated contrail detection algorithm (CDA) using five infrared channels available from the Moderate Resolution Imaging Spectrometer onboard Aqua satellite is used to determine linear coverage over Northern Hemisphere during 2006. Commercial aircraft flight data are employed filter false detections by CDA. The annual mean ranges 0.07% 0.40% for three different CDA sensitivities. Based on visual analyses, medium sensitivity provides best estimate of coverage, which...

Abstract The properties of contrail cirrus clouds are retrieved through analysis Terra and Aqua Moderate Resolution Imaging Spectroradiometer data for 21 cases spreading linear contrails. For these cases, enhanced the coverage by factors 2.4–7.6 depending on mask sensitivity. In dense air traffic areas, detection sensitivity is apparently reduced when older contrails overlap thus likely diminished during afternoon. mean optical depths effective particle sizes were 2–3 times 20% greater,...

Abstract Since the early 2000s, sea ice has experienced an increased rate of decline in thickness, extent and age. This new regime, coined ‘New Arctic’, is accompanied by a reshuffling energy flows at surface. Understanding magnitude nature this feedbacks therein remains limited. A novel database presented that combines satellite observations, model output, reanalysis data with parcel drift tracks Lagrangian framework. dataset consists daily time series locations, snow conditions,...

The drivers of rapid Arctic climate change—record sea ice loss, warming SSTs, and a lengthening the melt season—compel us to understand how this complex system operates use knowledge enhance predictability. Changing energy flows sparked by decline, spotlight atmosphere-surface coupling processes as central function its change response. Despite this, representation surface turbulent flux parameterizations in models has not kept pace with our understanding. large uncertainty projections, role...

Abstract Partly cloudy pixel retrievals (PCPRs) of cloud properties for marine stratocumulus were compared with those the 1 km Moderate Resolution Imaging Spectroradiometer (MODIS) product (MOD06). In addition, fractional cover obtained from PCPRs applied to MODIS radiances was that derived 250 m mask (MOD35). The comparisons made pixels overcast and only partially covered by clouds. Accounting failed in both MOD06 leads suggestion regional be estimated terms lower upper limits. average...

Abstract. Arctic clouds exhibit a robust annual cycle with maximum cloudiness in fall and minimum winter. These variations affect energy flows the large influence on surface radiative fluxes. Contemporary climate models struggle to reproduce observed cloud amount significantly disagree each other. The goal of this analysis is quantify influencing factors that contribute winter-summer differences, as these seasons are primarily responsible for model discrepancies observations. We find...

An automated contrail detection algorithm (CDA) is developed to exploit six of the infrared channels on 1-km MODerate-resolution Imaging Spectroradiometer (MODIS) Terra and Aqua satellites. The CDA refined balanced using visual error analysis. It applied MODIS data taken by over United States during 2006 2008. results are consistent with flight track data, but differ markedly from earlier analyses. Contrail coverage a factor 4 less than other retrievals retrieved optical depths radiative...

Arctic clouds play a key role in climate variability and change; however, contemporary models struggle to simulate cloud properties accurately. Model-simulated are determined by the physical parameterizations their interactions within model configuration. Quantifying effects of individual parameterization changes on model-simulated informs efforts improve provides insights system behavior. This study quantities influence schemes low Hadley Centre Global Environmental Model 3 atmospheric...

Abstract Arctic clouds play a key role in climate variability and change; however, contemporary models struggle to simulate cloud properties accurately. Model‐simulated are determined by the physical parameterizations their interactions within model configuration. Quantifying effects of individual parameterization changes on model‐simulated informs efforts improve provides insights system behavior. This study quantities influence scheme low Hadley Center Global Environmental Model 3...

Abstract. Since the early 2000s, sea ice has experienced an increased rate of decline in thickness and extent transitioned to a seasonal cover. This shift thinner, 'New Arctic' is accompanied by reshuffling energy flows at surface. Understanding magnitude nature this feedbacks therein remains limited. A novel database presented that combines satellite observations, model output, reanalysis data with daily parcel drift tracks produced Lagrangian framework. dataset consists time series...