Stratospheric and Tropospheric Flux Contributions to the Polar Cap Energy Budgets

2021 ◽  
pp. 1-49
Author(s):  
Christopher J. Cardinale ◽  
Brian E. J. Rose ◽  
Andrea L. Lang ◽  
Aaron Donohoe
Keyword(s):  
Energy Budget ◽  
Vertical Structure ◽  
Lower Troposphere ◽  
Longwave Radiation ◽  
Surface Energy Budget ◽  
The Arctic ◽  
Energy Budgets ◽  
Polar Regions ◽  
Static Energy ◽  
Arctic Surface

AbstractThe flux of moist static energy into the polar regions plays a key role in the energy budget and climate of the polar regions. While usually studied from a vertically integrated perspective (Fwall), this analysis examines its vertical structure, using the NASA-MERRA-2 reanalysis to compute climatological and anomalous fluxes of sensible, latent, and potential energy across 70°N and 65°S for the period 1980–2016. The vertical structure of the climatological flux is bimodal, with peaks in the mid- to lower-troposphere and mid- to upper-stratosphere. The near zero flux at the tropopause defines the boundary between stratospheric (Fstrat) and tropospheric (Ftrop) contributions to Fwall. Especially at 70°N, Fstrat is found to be important to the climatology and variability of Fwall, contributing 20.9 Wm−2 to Fwall (19% of Fwall) during the winter and explaining 23% of the variance of Fwall. During winter, an anomalous poleward increase in Fstrat preceding a sudden stratospheric warming is followed by an increase in outgoing longwave radiation anomalies, with little influence on the surface energy budget of the Arctic. Conversely, a majority of the energy input by an anomalous poleward increase in Ftrop goes toward warming the Arctic surface. Ftrop is found to be a better metric than Fwall for evaluating the influence of atmospheric circulations on the Arctic surface climate.

The Arctic surface energy budget as simulated with the IPCC AR4 AOGCMs

2007 ◽  
Vol 29 (2-3) ◽  
pp. 131-156 ◽  
Author(s):  
Asgeir Sorteberg ◽  
Vladimir Kattsov ◽  
John E. Walsh ◽  
Tatyana Pavlova
Keyword(s):  
Surface Energy ◽  
Energy Budget ◽  
Surface Energy Budget ◽  
The Arctic ◽  
Ipcc Ar4 ◽  
Arctic Surface

Interannual Variability in Arctic Surface Energy Fluxes and their Drivers

2021 ◽  
Author(s):  
Raleigh Grysko ◽  
Jacqueline Oehri ◽  
Gabriela Schaepman-Strub
Keyword(s):  
Surface Energy ◽  
Interannual Variability ◽  
Energy Budget ◽  
Climate Warming ◽  
Atmospheric Stability ◽  
Surface Energy Budget ◽  
The Arctic ◽  
Energy Fluxes ◽  
Surface Energy Fluxes ◽  
Arctic Surface

<div> <p>The Arctic is undergoing amplified climate warming, and temperature and precipitation are predicted to increase even more in the future. Increased climate warming is indicative of changes in the surface energy budget, which lies at the heart of the carbon and water budget. The surface energy budget is an important driver of many earth system processes, and yet has received little attention in the past.</p> </div><div> <p>The goal of this study is to further develop our understanding in the spatio-temporal variability of Arctic surface energy fluxes. Specifically, we will investigate the magnitude and dependence on changes in energy flux drivers interannually at different sites across the Arctic. We used<span> </span><em>in situ</em><span> </span>data from 10 sites gathered from the FLUXNET2015, Arctic Observatory Network, and European Fluxes Database Center repositories. All study sites are of 60° N or higher and spread across the Arctic. The chosen sites include Chokurdakh, Russia (147.5° E, 70.8° N), Cherskiy, Russia (161.3° E, 68.6° N), Kaamanen,, Finland (27.3° E, 69.1° N), Imnavait Creek, USA (-149.3° E, 68.6° N), Zackenberg Heath, Greenland (-20.6° E, 74.5° N), Tiksi, Russia (128.9° E, 71.6° N), Sodankyla, Finland (26.6° E, 67.4° N), Poker Flat, USA (-147.5° E, 65.1° N), Nuuk, Greenland (-51.4° E, 64.1° N), and Samoylov, Russia (126.5° E, 72.4° N). Using these data, we analyzed the interannual variability of surface energy fluxes including net radiation, sensible, latent, and ground heat fluxes, and Bowen ratio including their dependence on potential drivers, such as temperature, wind speed, atmospheric stability, and vapor pressure deficit.</p> </div><p>Our results on interannual variability in surface energy fluxes and flux drivers inform long term climate model simulations across the Arctic, which is critical for the improved prediction of the state and development of the surface energy budget and drivers under current and future conditions in this vulnerable, rapidly changing, and understudied region.</p>

scholarly journals Arctic Summer Airmass Transformation, Surface Inversions, and the Surface Energy Budget

2019 ◽  
Vol 32 (3) ◽  
pp. 769-789 ◽  
Author(s):  
Michael Tjernström ◽  
Matthew D. Shupe ◽  
Ian M. Brooks ◽  
Peggy Achtert ◽  
John Prytherch ◽  
...  
Keyword(s):  
Heat Flux ◽  
Surface Energy ◽  
Sea Ice ◽  
Energy Budget ◽  
Longwave Radiation ◽  
Temperature Inversion ◽  
Surface Energy Budget ◽  
Surface Heating ◽  
The Arctic ◽  
Turbulent Heat

During the Arctic Clouds in Summer Experiment (ACSE) in summer 2014 a weeklong period of warm-air advection over melting sea ice, with the formation of a strong surface temperature inversion and dense fog, was observed. Based on an analysis of the surface energy budget, we formulated the hypothesis that, because of the airmass transformation, additional surface heating occurs during warm-air intrusions in a zone near the ice edge. To test this hypothesis, we explore all cases with surface inversions occurring during ACSE and then characterize the inversions in detail. We find that they always occur with advection from the south and are associated with subsidence. Analyzing only inversion cases over sea ice, we find two categories: one with increasing moisture in the inversion and one with constant or decreasing moisture with height. During surface inversions with increasing moisture with height, an extra 10–25 W m−2 of surface heating was observed, compared to cases without surface inversions; the surface turbulent heat flux was the largest single term. Cases with less moisture in the inversion were often cloud free and the extra solar radiation plus the turbulent surface heat flux caused by the inversion was roughly balanced by the loss of net longwave radiation.

scholarly journals Impacts of Shallow Convection on MJO Simulation: A Moist Static Energy and Moisture Budget Analysis

2013 ◽  
Vol 26 (8) ◽  
pp. 2417-2431 ◽  
Author(s):  
Qiongqiong Cai ◽  
Guang J. Zhang ◽  
Tianjun Zhou
Keyword(s):  
Boundary Layer ◽  
Deep Convection ◽  
Lower Troposphere ◽  
Longwave Radiation ◽  
Reanalysis Data ◽  
Specific Humidity ◽  
Moist Static Energy ◽  
Shallow Convection ◽  
Budget Analysis ◽  
Static Energy

Abstract The role of shallow convection in Madden–Julian oscillation (MJO) simulation is examined in terms of the moist static energy (MSE) and moisture budgets. Two experiments are carried out using the NCAR Community Atmosphere Model, version 3.0 (CAM3.0): a “CTL” run and an “NSC” run that is the same as the CTL except with shallow convection disabled below 700 hPa between 20°S and 20°N. Although the major features in the mean state of outgoing longwave radiation, 850-hPa winds, and vertical structure of specific humidity are reasonably reproduced in both simulations, moisture and clouds are more confined to the planetary boundary layer in the NSC run. While the CTL run gives a better simulation of the MJO life cycle when compared with the reanalysis data, the NSC shows a substantially weaker MJO signal. Both the reanalysis data and simulations show a recharge–discharge mechanism in the MSE evolution that is dominated by the moisture anomalies. However, in the NSC the development of MSE and moisture anomalies is weaker and confined to a shallow layer at the developing phases, which may prevent further development of deep convection. By conducting the budget analysis on both the MSE and moisture, it is found that the major biases in the NSC run are largely attributed to the vertical and horizontal advection. Without shallow convection, the lack of gradual deepening of upward motion during the developing stage of MJO prevents the lower troposphere above the boundary layer from being preconditioned for deep convection.

scholarly journals Eurasian Cooling Linked with Arctic Warming: Insights from PV Dynamics

2020 ◽  
Vol 33 (7) ◽  
pp. 2627-2644
Author(s):  
Yongkun Xie ◽  
Guoxiong Wu ◽  
Yimin Liu ◽  
Jianping Huang
Keyword(s):  
Vertical Structure ◽  
Diabatic Heating ◽  
Linear Trend ◽  
Three Dimensional ◽  
Lower Troposphere ◽  
The Arctic ◽  
Arctic Warming ◽  
Circulation Change ◽  
General Dynamics ◽  
Upper Level

AbstractThe three-dimensional connections between Eurasian cooling and Arctic warming since 1979 were investigated using potential vorticity (PV) dynamics. We found that Eurasian cooling can be regulated by Arctic warming through PV adaptation and PV advection. Here, PV adaptation refers to the adaptation of PV to forcing and coherent dynamic–thermodynamic adaptation to PV change. In a PV perspective, first, the anticyclonic circulation change over the Arctic is produced by a negative PV change through PV adaptation, in which the change means the linear trend from 1979 to 2017. The negative PV change is directly regulated by Arctic warming because the vertical structure of Arctic warming is stronger at lower levels, which generates a negative PV change through the diabatic heating effect. Second, the circulation change produces a change in horizontal PV advection due to the existence of climatological PV gradients. Thus, as a balanced result, both the circulation change and PV change extend to the midlatitudes through horizontal PV advection and PV adaptation. Eventually, Eurasian cooling at the surface and in the lower troposphere is dominated by PV changes at the surface through PV adaptation. Meanwhile, enhanced Eurasian cooling in the middle troposphere is dominated by top-down influences of upper-level PV change through PV adaptation. Nevertheless, the upper-level PV changes are still contributed to by horizontal PV advection associated with Arctic warming. Overall, the general dynamics connecting Eurasian cooling with Arctic warming are demonstrated in a PV view.

scholarly journals Influence of Precipitation Assimilation on a Regional Climate Model’s Surface Water and Energy Budgets

2007 ◽  
Vol 8 (4) ◽  
pp. 642-664 ◽  
Author(s):  
Ana M. B. Nunes ◽  
John O. Roads
Keyword(s):  
Surface Water ◽  
Energy Budget ◽  
Prediction Models ◽  
Regional Climate ◽  
Longwave Radiation ◽  
Specific Humidity ◽  
Climate Simulation ◽  
Energy Budgets ◽  
Near Surface ◽  
Regional Reanalysis

Abstract Initialization of the moisture profiles has been used to overcome the imbalance between analysis schemes and prediction models that generates the so-called spinup problem seen in the hydrological fields. Here precipitation assimilation through moisture adjustment has been proposed as a technique to reduce this problem in regional climate simulations by adjusting the specific humidity according to 3-hourly North American Regional Reanalysis rain rates during two simulated years: 1988 and 1993. A control regional simulation provided the initial condition fields for both simulations. The precipitation assimilation simulation was then compared to the control regional climate simulation, reanalyses, and observations to determine whether assimilation of precipitation had a positive influence on modeled surface water and energy budget terms. In general, rainfall assimilation improved the regional model surface water and energy budget terms over the conterminous United States. Precipitation and runoff correlated better than the control and the global reanalysis fields to the regional reanalysis and available observations. Upward shortwave and downward short- and longwave radiation fluxes had regional seasonal cycles closer to the observed values than the control, and the near-surface temperature anomalies were also improved.

scholarly journals The Changing Energy Balance of the Polar Regions in a Warmer Climate

2013 ◽  
Vol 26 (10) ◽  
pp. 3112-3129 ◽  
Author(s):  
Lennart Bengtsson ◽  
Kevin I. Hodges ◽  
Symeon Koumoutsaris ◽  
Matthias Zahn ◽  
Paul Berrisford
Keyword(s):  
Polar Region ◽  
Energy Transport ◽  
Climate Model ◽  
Radiant Energy ◽  
Surface Radiation ◽  
The Arctic ◽  
Polar Regions ◽  
Energy Fluxes ◽  
Intergovernmental Panel ◽  
Static Energy

Abstract Energy fluxes for polar regions are examined for two 30-yr periods, representing the end of the twentieth and twenty-first centuries, using data from high-resolution simulations with the ECHAM5 climate model. The net radiation to space for the present climate agrees well with data from the Clouds and the Earth’s Radiant Energy System (CERES) over the northern polar region but shows an underestimation in planetary albedo for the southern polar region. This suggests there are systematic errors in the atmospheric circulation or in the net surface energy fluxes in the southern polar region. The simulation of the future climate is based on the Intergovernmental Panel on Climate Change (IPCC) A1B scenario. The total energy transport is broadly the same for the two 30-yr periods, but there is an increase in the moist energy transport on the order of 6 W m−2 and a corresponding reduction in the dry static energy. For the southern polar region the proportion of moist energy transport is larger and the dry static energy correspondingly smaller for both periods. The results suggest a possible mechanism for the warming of the Arctic that is discussed. Changes between the twentieth and twenty-first centuries in the northern polar region show the net ocean surface radiation flux in summer increases ~18 W m−2 (24%). For the southern polar region the response is different as there is a decrease in surface solar radiation. It is suggested that this is caused by changes in cloudiness associated with the poleward migration of the storm tracks.

Eurasian cooling linked with Arctic warming: Insights from PV dynamics

2020 ◽  
Author(s):  
Yongkun Xie ◽  
Guoxiong Wu ◽  
Yimin Liu
Keyword(s):  
Vertical Structure ◽  
Diabatic Heating ◽  
Linear Trend ◽  
Three Dimensional ◽  
Lower Troposphere ◽  
The Arctic ◽  
Arctic Warming ◽  
Circulation Change ◽  
General Dynamics ◽  
Upper Level

<p>The three-dimensional connections between Eurasian cooling and Arctic warming since 1979 were investigated using potential vorticity (PV) dynamics. We found that Eurasian cooling can be regulated by Arctic warming through PV adaptation and PV advection. Here, PV adaptation refers to the adaptation of PV to forcing and coherent dynamic/thermodynamic adaptation to PV change. In a PV perspective, first, the anticyclonic circulation change over the Arctic is produced by a negative PV change through PV adaptation, in which the change means the linear trend from 1979~2017. The negative PV change is directly regulated by Arctic warming because the vertical structure of Arctic warming is stronger at lower levels, which generates a negative PV change through the diabatic heating effect. Second, the circulation change produces a change in horizontal PV advection due to the existence of climatological PV gradients. Thus, as a balanced result, both the circulation change and PV change extend to mid-latitude through horizontal PV advection and PV adaptation. Eventually, Eurasian cooling at the surface and in the lower troposphere is dominated by PV changes at the surface through PV adaptation. Meanwhile, enhanced Eurasian cooling in the middle troposphere is dominated by top-down influences of upper-level PV change through PV adaptation. Nevertheless, the upper-level PV changes are still contributed by horizontal PV advection associated with Arctic warming. Overall, the general dynamics connecting Eurasian cooling with Arctic warming is demonstrated in a PV view.</p>

scholarly journals Dr. Yanai’s Contributions to the Discovery and Science of the MJO

2016 ◽  
Vol 56 ◽  
pp. 4.1-4.18 ◽  
Author(s):  
Eric D. Maloney ◽  
Chidong Zhang
Keyword(s):  
Kinetic Energy ◽  
Potential Energy ◽  
Energy Budget ◽  
Momentum Transport ◽  
Energy Budgets ◽  
Equatorial Waves ◽  
Madden Julian Oscillation ◽  
Moist Static Energy ◽  
Moist Static Energy Budget ◽  
Static Energy

Abstract This chapter reviews Professor Michio Yanai’s contributions to the discovery and science of the Madden–Julian oscillation (MJO). Professor Yanai’s work on equatorial waves played an inspirational role in the MJO discovery by Roland Madden and Paul Julian. Professor Yanai also made direct and important contributions to MJO research. These research contributions include work on the vertically integrated moist static energy budget, cumulus momentum transport, eddy available potential energy and eddy kinetic energy budgets, and tropical–extratropical interactions. Finally, Professor Yanai left a legacy through his students, who continue to push the bounds of MJO research.

Sign in / Sign up

Export Citation Format

Share Document