https://yuzheny.com/about daily 1.0 2025-09-27 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/a3c009e4-b659-4a5c-b0f9-b2fb8442484e/Yuzhen+Yan+Tongji.jpg About https://yuzheny.com/fieldwork daily 0.75 2023-11-03 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1698980296350-AIVDJGVKVTQHLDTNOSLN/IMG_3406.jpg Fieldwork - Allan Hills I-165 crew with the first ice core drilled in 2022 season (Back row, left to right) Sarah Shackleton, Jacob Morgan, Yuzhen Yan (Mid row) Jonathan Hayden, Julia M. Peterson, Mike Jayred, Elizabeth Morton (Front row) Austin Carter https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428121801-ABBMQ6669XY1VIA8H90X/IMG_1893.JPG Fieldwork - Arriving in Antarctica We flew from Christchurch, New Zealand on a C17 “Globemaster” capable of landing on ice (!) https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428163176-RB1YQKKK283E8T9OZUMQ/IMG_2023.JPG Fieldwork - Flying out, to the wild After spending a week at McMurdo for safety training, we embarked on our 7-week journey to Allan Hills Blue Ice Areas … https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540437609800-RT8MVQRCUTLKW61QELMS/IMG_2030.JPG Fieldwork - New life starts! Upon landing in the field, we immediately began to establish a camp, our little home thousands of miles away from home. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428197485-2MU61DB6ISS5QCSMBIX0/IMG_2167.JPG Fieldwork - Life in tents Those little pyramids are our living room (except the last one, which is the restroom). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428277229-89L2O1U8NY400X9U0WDS/IMG_3165.JPG Fieldwork - Life after storm During the middle of the field season, we got hit hard by a major Antarctic storm. See the pile of snow behind the tents? That’s the power of nature. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428207480-JG2S1MKC2SR2U20KOPR9/IMG_2475.JPG Fieldwork - Gauging the ice Here, Dr. Sean Mackay is doing GPR survey and attempting to measure the ice thickness. The goal is to locate the next drilling site where old ice could be found. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540437711544-9S10Y6D2R61OJAWOO7FU/IMG_2064.JPG Fieldwork - All system go! We spent two full days to set up the drill tent and the drill, including dig out this little trench. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428217341-CHZAF2EPWWQR5WS41J93/IMG_2512.JPG Fieldwork - Ice drilling in process A freshly drilled ice core, in a barrel. We used a three-inch drill that is optimized for mobility and efficiency. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540437353049-SAJ94SWUUZPHBBIZZVCZ/IMG_3143.JPG Fieldwork - An ice core is born Dr. John Higgins (left) and Mike Waszkiewicz (right) holding the drill barrel that carries the cylindrical core. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428177509-EO4POCV9I97HC22VV04M/IMG_2074.JPG Fieldwork - First batch of cores of the season! Our very first batch of ice cores drilled in the entire field season. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428400751-FQ4PZI0FODDY95UNX6WO/IMG_2510.JPG Fieldwork - Fossil air inside bubbles Inside the ice are air bubbles that are hundreds of thousand years (more precisely speaking, 300 to 500 ka). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540437792773-3723B0GJPEOYI6335AET/IMG_2587.JPG Fieldwork - Outside the tent The drill is powered by a 5 kW generator located outside the tent. Also shown are two skidoos, our primary means of transportation in the field. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428252901-BBQIMWJ29NBXGPG2XS2A/IMG_3053.JPG Fieldwork - Hit the rock bottom We knew the we’ve exhausted all the ice from the borehole because of the damage to the drill bits (R.I.P.). Time to move on to the next site! https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428262940-SYICJHE107GNPA7OOA09/IMG_3059.JPG Fieldwork - Knock down that tent Once we finished all the drilling, the drill tent was struck down. Here John Higgins (left) and Preston Kemeny (right) are examining the poles and fabrics. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540428292147-QCKKHD76LAONOFW7V9YY/IMG_3200.JPG Fieldwork - To hiking! While life in Antarctica is in general quite boring, we managed to have some fun in the great outdoor. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540429853818-32G3U2FD8TFAO80AHUEA/IMG_3072.JPG Fieldwork - Visualizing glacial flow Ice in Allan Hills is constantly flowing. The curved line (actually a tephra layer) here demonstrates the differential flow of the ice. https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540429933299-JJI16ICPNQ1SJSP42GQK/IMG_3214.JPG Fieldwork - Allan Hills overlook Because of the bedrock topography, the surface of the Allan Hills Blue Ice Areas is not flat. Instead, interesting features like this are common throughout the area. https://yuzheny.com/external-links daily 0.75 2021-10-16 https://yuzheny.com/old-ice daily 0.75 2021-12-06 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540493243215-O462TJU4PH1C1MJEPBC0/Paper_Fig1.png Searching for “Old Ice” in Allan Hills, East Antarctica Figure 1. Depth-age relationship of ALHIC1502 (blue) and ALHIC1503 (red) ice cores. Data in circles are measured at Princeton University (PU; Higgins et al, 2015). New measurements made at Scripps Institution of Oceanography (SIO) are plotted in squares. Error bars represent the the external reproducibility (1σ; 110 kyr and 220 kyr for samples measured at SIO and PU, respectively) of the measurement or 10% of the sample age, whichever is greater. Grey bar highlights the section where >1 Ma ice is present. In the right inset, Ar-ages are plotted against distance from the bedrock. https://yuzheny.com/mpt daily 0.75 2023-11-03 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540493043485-D67OG4P5GVB77I55VZ91/LR04Raymo.001.jpeg Pleistocene glacial cycles Figure 1. Climate evolution over the past 3 Ma recorded in the oxygen isotope compositions of benthic foraminifera shells [data from Lisiecki and Raymo (2005)] https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634174666808-PQXUDKP1BFBUMCEYI9X2/Paper_Fig2_Hollow.jpg Pleistocene glacial cycles - Make it stand out Figure 2. Climate properties over the past 2.9 Myr documented in ice core (A-D) and benthic foram (E) records. A detailed description of each panel is presented in Yan et al (2019). https://yuzheny.com/personal daily 0.75 2021-10-16 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608931808056-RCCV0DF5639A48DQH9PR/IMG5528.JPG Personal - Bisti/De-Na-Zin Wilderness, New Mexico, USA https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608930935182-OR7DA5CQD6O6DEIOQNJM/IMG_DSC8512_AfgaVista100.jpg Personal - Cerro de la Silla, Monterrey, Mexico https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608931983333-AW3APKZ9V14CT89L71KE/IMG6708.JPG Personal - Grand Staircase-Escalante National Monument, Utah, USA https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1609007502199-GNWXAH0RPFBX5MDD3LEQ/IMG_DSC8351_AfgaVista100.jpg Personal - Parque la Huasteca, Santa Catarina, Mexico https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608934098208-KYKMAJ1H69JD2NTGDJZ5/IMG2484.JPG Personal - Coyote Buttes North "The Wave", Arizona, USA https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608933393706-RNXSZACU99UPA94AL4G5/IMG7843.JPG Personal - Easter Island, Chile https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1698980873372-XJR7YJBGKHTOD9GYTVIX/_DSC3542.jpg Personal - Chobe National Park, Botswana https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1609016703566-8VFJZ5QJTF08XF50J5C7/IMG_DSC4629.jpg Personal - Athens, Greece https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608932659146-A0D56X5LX81CRW3NL9X8/IMG3661.JPG Personal - Scottish Highlands, UK https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1609007642135-747ZB4D61O29SFRVE263/IMG7630.JPG Personal - Rottnest Island, Australia https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1608934618596-R3H0DALT3BREDIS9WOPO/IMG2842.JPG Personal - Zhangye Danxia Geopark, Gansu, China https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1609019852885-1BDHZP4WR4GJADI7TDTX/DSC7695_1.jpg Personal - Shanghai, China https://yuzheny.com/oxygen daily 0.75 2023-11-11 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634170668936-9BK1MYJZZ12H5C0K1KUB/Picture1.png History of atmospheric oxygen - Make it stand out Figure 1. A record of atmospheric oxygen based on four deep ice cores, modified from Stolper et al (2016). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634175196600-DZU27SP26DC6630OSJ99/Figure3_capital%2Blabel.jpg History of atmospheric oxygen - Make it stand out Figure 3. Paired δO2/N2-δAr/N2 as measured in Allan Hills ice core samples, binned according to their age (dashed lines represent the 95% confidence interval of the regression slopes). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634172798214-5KUSU5A9LJATDQOKTOER/Fig1_3.5x3.5.jpg History of atmospheric oxygen - Make it stand out Figure 2. A schematic illustration of paired δO2/N2-δAr/N2 approach (not to scale). https://yuzheny.com/wais daily 0.75 2021-12-06 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634325986789-9X433AVV39I9KHA3583Q/OldFig1w.jpg Cryosphere changes - Make it stand out Figure 1. Map of Antarctica, where the location of the S27 ice core is marked in star. (map source: Alexrk2, Wikimedia Commons; licensed under the Creative Commons Attribution-Share Alike 3.0 Unported License). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634326774855-BUFP99Z6QLJOHG45QSQS/Fig9_noiso_T_uncert-01.jpg Cryosphere changes - Make it stand out Figure 2. Paleoclimate records during Termination II and the Last Interglacial. A detailed description of each panel is presented in Yan et al (2021). https://yuzheny.com/glaciology daily 0.75 2022-07-20 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1540492782344-WE7JBX2X3S3UYG783MDX/horizontal_ice.png Blue ice glaciology - Make it stand out Figure 1. Schematics of the glaciological setting near Allan Hills Blue Ice Areas, modified from Whillans and Cassidy (1983). Courtesy of Dr. John Higgins. https://yuzheny.com/atm-chemistry daily 0.75 2023-11-03 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/26fd0483-138f-4d4e-8b87-c091621c3b23/D36_schematics.png Atmosphere chemistry - Make it stand out Figure 1. Schematic of the atmospheric Δ36 budget, from Yeung et al (2016). https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/5809025a-ea3b-44f4-adec-e73bad18393a/Artboard+1%40600x-100.jpg Atmosphere chemistry - Make it stand out Figure 2. (a) Temporal evolution of Δ36 from the Penultimate Glacial Maximum (PGM: 147–135 ka; mean Δ36 = 2.11‰; 1σ = 0.04‰; N = 25) to the Last Interglacial (LIG: 130–115 ka; mean Δ36 = 2.07‰; 1σ = 0.04‰; N = 16) and (b) probability density distributions of mean atmospheric Δ36 values obtained from bootstrap resampling of PGM and LIG data from this study as well as present day (PD), preindustrial (PI) and Last Glacial Maximum (LGM) data reported previously (Banerjee et al., 2022; Yeung et al., 2019). Error bars represent the analytical uncertainties of the replicated Δ36 measurements, calculated as the pooled standard deviation (0.04‰) divided by the square root of the number of actual replicates. For samples with no replicates, no error bars are shown and we assume the uncertainty to be 0.04‰. The 7-kyr moving average (bold black curve) of measured Δ36 values is bracketed by the 95% CI (gray shading). https://yuzheny.com/404 daily 0.75 2021-12-06 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/1634328775759-LKT8HXK6UTF2BPLR3P4C/IMG_3061.jpg 404 - Make it stand out Whatever it is, the way you tell your story online can make all the difference. https://yuzheny.com/edc-test daily 0.75 2021-11-07 https://images.squarespace-cdn.com/content/v1/5bd0f07c65019f2935162397/499f235a-1a98-48f6-b719-b93caba82c41/Fig2_5x4.jpg EDC Test