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How likely is the nearly four-fold warming in the Arctic, as observed in 1979–2021? To answer this question, we investigate all possible AA 43 ratios starting after 1970 and ending by 2040 from all four climate model ensembles (see Section “Comparison between simulated and observed Arctic amplification”). While these 43-year periods overlap, and therefore not fully independent, we consider all these periods together because the internal climate variability is not expected to be in phase in models and observations. Update 09/22/2021: We've changed Multi-Device Pairing from 'No' to 'Bluetooth + Console/Non-BT Wireless' as these headphones can connect to a PS4 console and a Bluetooth device at the same time. You first connect the headphones' dongle to your PS4. Next, you press the headphones' 'Bluetooth' button to pair them with a phone. Once paired to both devices, you can hear audio from both devices simultaneously. As a result, we have updated our review, and the scoring of this box has changed. Looking at the spreads of AA 43 in SMILEs, we find that they explain a majority of the total CMIP5 and CMIP6 spread, suggesting that the model uncertainty plays a relatively small role in this comparison (Fig. 6). The observed AA 43 in 1979–2021 (red line) is fully outside the spread of MPI-GE (Fig. 6c), thus giving a probability p ≈ 0.00. This means explicitly that MPI-GE does not capture the observed Arctic amplification as none of its 100 ensemble members can simulate sufficiently strong AA 43 in any 43-year periods between 1970 and 2040.
Singh, H., Rasch, P. & Rose, B. Increased ocean heat convergence into the high latitudes with CO 2 doubling enhances polar-amplified warming. Geophys. Res. Lett. 44, 10583–10591 (2017). Screen, J. & Simmonds, I. The central role of diminishing sea ice in recent Arctic temperature amplification. Nature 464, 1334–1337 (2010). The earliest inhabitants of North America's central and eastern Arctic are referred to as the Arctic small tool tradition (AST) and existed c. 2500 BCE. AST consisted of several Paleo-Eskimo cultures, including the Independence cultures and Pre-Dorset culture. [17] [18] The Dorset culture ( Inuktitut: Tuniit or Tunit) refers to the next inhabitants of central and eastern Arctic. The Dorset culture evolved because of technological and economic changes during the period of 1050–550 BCE. With the exception of the Quebec/ Labrador peninsula, the Dorset culture vanished around 1500 CE. [19] Supported by genetic testing, evidence shows that descendants of the Dorset culture, known as the Sadlermiut, survived in Aivilik, Southampton and Coats Islands, until the beginning of the 20th century. [20] Ogura, T. & Abe-Ouchi, A. Influence of the Antarctic ice sheet on southern high latitude climate during the Cenozoic: albedo vs topography effect. Geophys. Res. Lett. 28, 587–590 (2001).The orography of the AIS, which towers nearly 4 km above sea level at its highest, is possibly the most obvious factor which could account for weak (or non-existent) warming over the Antarctic continent. The presence of the AIS has a substantial impact on the mean state dynamics and thermodynamics of the Southern Hemisphere (see, e.g., 14, 15, 16, 17, 18, 19). Global climate model (GCM) experiments in which Antarctic continental orography is flattened exhibit weaker baroclinicity over the Southern Ocean, greater baroclinicity over the Antarctic continent, and, consequently, more frequent incursion of midlatitude eddies over the Antarctic plateau 14, 20, 21. At the same time, (equatorward) katabatic flow away from the Antarctic continent ceases when Antarctic orography is flattened, and the Southern hemispheric polar cell vanishes 15, 16. Other studies have highlighted the existence of a negative greenhouse effect over the Antarctic continent: the instantaneous outgoing longwave radiation at the top-of-atmosphere increases, rather than decreases, with higher levels of atmospheric CO 2 50, 51, 52. That negative greenhouse effect, which only occurs in some months of the year, owes its existence to the tropospheric temperature inversion over the extremely cold Antarctic surface, and is enhanced by the relative absence of tropospheric water vapor in that region 53. While that negative greenhouse effect has indeed been observed from satellites (as documented by 53), it dissipates rapidly following abrupt CO 2-quadrupling in fully coupled GCMs due to fast stratospheric adjustments 54, and does not result in a cooling of the Antarctic surface. Furthermore, Flanner et al. 55 show that the net surface longwave radiative impact of greenhouse gases will always tend to heat the surface at high latitudes because of the local temperature inversion, regardless of whether the greenhouse effect is positive or negative at the top-of-atmosphere. In the present study, we do find that the net (downward) surface longwave flux with CO 2-doubling is greater when Antarctic orography is flattened. However, we are leery to attribute the surface-amplified warming with flat orography to this factor: analysis of surface radiative kernels indicates that anomalies in the downward longwave flux at the surface primarily arise as a consequence of surface temperature anomalies, rather being the cause of those anomalies 56. A thorough assessment of instantaneous radiative forcing, and of the accompanying rapid adjustments, is outside the scope of the present study, as we are here interested in the Antarctic surface climate response to CO 2-doubling at quasi-equilibrium, not in the details of the radiative forcing and adjustment immediately following the doubling of CO 2. Boswell, Randy (28 May 2008). "Conference could mark start of Arctic power struggle". canada.com. Archived from the original on 4 March 2009 . Retrieved 6 June 2008.
When Antarctic orography is flattened, we find a larger increase in CO 2-forced latent heat transport toward the Antarctic continent than when orography is at its present-day height. This is evident in both CESM1.1 and CCSM4.0 (Fig. 4, panels a and b, respectively; compare solid and dashed blue lines), corresponding to a 0.05 PW increase in latent heat transport across 70S in both models; this represents a 100% increase in the poleward latent heat transport response to CO 2-doubling in CCSM4.0, and a 50% increase in CESM1.1. Oleson, K. et al. Technical description of version 4.0 of the Community Land Model (CLM). Technical Report TN-478 + STR. (National Center for Atmospheric Research, 2010). Parish, T. On the role of Antarctic katabatic winds in forcing large-scale tropospheric motions. J. Atmos. Sci. 49, 1374–1385 (1991). Tedesco, M.; Mote, T.; Fettweis, X.; Hanna, E.; Jeyaratnam, J.; Booth, J. F.; Datta, R.; Briggs, K. (2016). "Arctic cut-off high drives the poleward shift of a new Greenland melting record". Nature Communications. 7: 11723. Bibcode: 2016NatCo...711723T. doi: 10.1038/ncomms11723. PMC 4906163. PMID 27277547.The spread of simulated AA in CMIP5 and CMIP6 realizations arises from both internal climate variability and the inter-model spread. To assess the role of internal variability in the AA uncertainty, we next consider the two single-model initial-condition large ensembles (hereafter SMILEs). The individual members of SMILEs are initialized from different initial conditions with identical external forcing; thus the spread in these ensembles is solely due to internal variability 51, 52. In principle, SMILEs are thus powerful tool to quantify the internal variability of the climate system.
Main article: Global warming in the Arctic Arctic sea ice coverage as of 2007 compared to 2005 and compared to 1979–2000 average Mechoso, C. The atmospheric circulation around Antarctica: linear stablity and finite amplitude interactions with migrating cyclones. J. Atmos. Sci. 37, 2209–2233 (1980). Hwang, Y.-T. & Frierson, D. Increasing atmospheric poleward energy transport with global warming. Geophys. Res. Lett. 37, L24807 (2010).Flanner, M., Huang, X., Chen, X. & Krinner, G. Climate response to negative greenhouse gas radiative forcing in polar winter. Geophys. Res. Lett. 45, 1997–2004 (2018). To assess the accuracy of the four datasets applied in our study (GISTEMP, BEST, HadCRUT5, ERA5) in the Arctic, we conducted a validation against the Global Historical Climatology Network monthly (GHCN-M) station data 67. We used the station data which was bias-adjusted for non-climatic effects (indicated by the suffix “.qcf” in the GHCN-M database). We selected all the stations located north of 66.5 ∘N that had at least 39 years of data over the 43-year period of 1979–2021. In total, these criteria resulted in 87 stations. We calculated the temperature trends for each station, and compared them with the average across the four gridded datasets. These results are shown in Fig. S 1. The median difference between the trends estimated from the gridded data and the 87 station observations (gridded minus stations) is −0.019 ∘C decade −1. Therefore, we conclude that the average of the four gridded temperature datasets generally captures well the temporal trends of the near-surface mean temperature in the Arctic, which makes it suitable to be used as a basis of our study. Climate model data Chiang, J. C. & Bitz, C. M. Influence of high latitude ice cover on the marine intertropical convergence zone. Clim. Dyn. 25, 477–496 (2005). SteelSeries has rated the Arctis 9 Wireless at 20 hours of battery life on a single charge. Testing across two days, I landed at just under that. This is pretty great for a wireless headset, especially since I’m you're more likely to charge it between uses than, say, the best wireless mouse or any of the best wireless keyboards. Since it charges over Micro USB rather than the faster USB-C, charge time felt long (around 4-plus hours), but you can still use the headset wirelessly while it’s charging. Gibbon, Guy E.; Kenneth M. Ames (1998). Archaeology of prehistoric native America: an encyclopedia. Vol.1537 of Garland reference library of the humanities. Taylor & Francis. ISBN 978-0-8153-0725-9.