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The East Australian Current (EAC) is the western boundary current of the South Pacific Subtropical Gyre that transports warm tropical waters to higher southern latitudes and significantly impacts the climate of Australia and New Zealand. Modern observations show that the EAC has strengthened with rising global temperatures. However, little is known about the pre‐industrial variability of the EAC and the forcing mechanisms. Planktic foraminifera Globigerinoides ruber (white) Mg/Ca‐based sea surface temperature reconstructions offshore northeastern Australia between 15° and 26°S reveal an increase by ∼1.2°C after ∼1400 CE. We infer that the increase in temperature is related to a stronger EAC heat transport that is likely driven by a strengthening of the Southern Hemisphere subtropical gyre circulation due to a progressive shift of the Southern annular mode toward its positive phase and of El Niño‐Southern Oscillation toward more El Niño‐like conditions. Plain Language Summary: The East Australian Current (EAC) transports large amounts of heat out of the Western Pacific Warm Pool into the subtropics and subpolar regions, thereby regulating the local and global climate. The few existing reconstructions of past changes in transport and temperature of the EAC are contradictory resulting in a knowledge gap in long‐term variability of the southwest Pacific currents, which in turn hampers a reliable projection of future tropical and subtropical climate development. We use sea surface temperature reconstructions along the EAC path off northeastern Australia to estimate changes in the EAC heat transport over the past 4,000 years and its potential driving mechanisms. Our results reveal an increase in temperature after ∼1400 CE, which we relate to an intensification of the EAC strength. The strengthening of the EAC after ∼1400 CE is likely associated with a strengthening of the Southern Hemisphere subtropical gyre circulation due to a progressive shift of the Southern annular mode toward its positive phase and of El Niño‐Southern Oscillation toward more El Niño‐like conditions. Key Points: Mg/Ca‐based sea surface temperature reconstructions reveal an intensification of the East Australian Current (EAC) after ∼1400 CEA stronger EAC is likely driven by strengthening of the Southern Hemisphere subtropical gyre due to a Southern Annular Mode shift toward its positive phaseMore El Niño‐like conditions may also strengthen the EAC by an equatorward shift of the South Equatorial Current bifurcation latitude [ABSTRACT FROM AUTHOR]

SUMMARY: Food allergies are a major health issue worldwide. Modern breeding techniques such as genome editing via CRISPR/Cas9 have the potential to mitigate this by targeting allergens in plants. This study addressed the major allergen Bra j I, a seed storage protein of the 2S albumin class, in the allotetraploid brown mustard (Brassica juncea). Cotyledon explants of an Indian gene bank accession (CR2664) and the German variety Terratop were transformed using Agrobacterium tumefaciens harboring binary vectors with multiple single guide RNAs to induce either large deletions or frameshift mutations in both Bra j I homoeologs. A total of 49 T0 lines were obtained with up to 3.8% transformation efficiency. Four lines had large deletions of 566 up to 790 bp in the Bra j IB allele. Among 18 Terratop T0 lines, nine carried indels in the targeted regions. From 16 analyzed CR2664 T0 lines, 14 held indels and three had all four Bra j I alleles mutated. The majority of the CRISPR/Cas9‐induced mutations were heritable to T1 progenies. In some edited lines, seed formation and viability were reduced and seeds showed a precocious development of the embryo leading to a rupture of the testa already in the siliques. Immunoblotting using newly developed Bra j I‐specific antibodies revealed the amount of Bra j I protein to be reduced or absent in seed extracts of selected lines. Removing an allergenic determinant from mustard is an important first step towards the development of safer food crops. Significance Statement: Mustard is a significant elicitor of allergic reactions to food. The major allergen in brown mustard (Brassica juncea) is Bra j I, a 2S albumin seed storage protein. This is the first report of genome editing in B. juncea, and we mutated up to all four gene copies in this tetraploid plant resulting in plants with reduced levels or absence of Bra j I protein. [ABSTRACT FROM AUTHOR]

The integrated effects of ocean‐atmosphere dynamics on the temperature evolution in the western North Pacific marginal seas have remained elusive. In order to study mechanisms controlling southern Yellow Sea (YS) temperature changes, bottom water temperature (BWT) changes were reconstructed for the last 8.8 kyr by using the TEXL86 index, which archives temperature signal of the winter season Yellow Sea Warm Current. Our results reveal a series of abrupt multi‐centennial to millennial scale BWT changes (∼1°C), superimposed on a gradual long‐term cooling (>3°C) trend starting from ∼5 ka to the present. The YS BWT changes are positively correlated with subsurface water temperature changes in the Western Pacific Warm Pool (WPWP). The Western Pacific Warm Pool subsurface water cooling signal was most likely transmitted by the Kuroshio Current into the southern YS, highlighting the role of WPWP in influencing thermodynamics of the extratropical regions during the Holocene. Plain Language Summary: The Yellow Sea (YS) is a semi‐closed marginal sea located in the northwestern Pacific Ocean. During the winter season, the Yellow Sea Warm Current (YSWC) is driven by northwesterly winds, flowing into the southern YS along the west flank of the central trough. The YSWC, a continuation of the Kuroshio Current, brings warm equatorial Pacific water into the YS, leading to milder winters in the surrounding coastal cities compared with other cities on the same latitude in China. The YSWC is sensitive to changes in ocean‐atmosphere dynamics. However, its evolution during the Holocene is not well understood. We reconstruct the winter season temperature changes of the YSWC during the last 8.8 kyr. We found warm temperatures during the mid‐Holocene (8.8‐5 ka) and a gradual cooling trend over the last 5 kyr, which coincides with subsurface water temperature changes in the Western Pacific Warm Pool (WPWP). We suggest that the tropical subsurface water temperature changes of the WPWP are most likely transmitted via the Kuroshio Current into the YS. Our results shed new light on our understanding of the role played by the WPWP water masses in regulating subtropical ocean dynamics and climate during the mid‐to‐late Holocene. Key Points: The temperature evolution of the winter season Yellow Sea Warm Current was reconstructed over the past 8.8 kyrAbrupt multi‐centennial to millennial scale changes are superimposed on a gradual cooling trend starting from ∼5 ka to the presentWestern Pacific Warm Pool subsurface water cooling signal was transmitted by the Kuroshio Current into the southern Yellow Sea [ABSTRACT FROM AUTHOR]

During the middle Miocene, Earth's climate changed from a global warm period (Miocene Climatic Optimum) into a colder one with the expansion of the Antarctic ice sheet. This prominent climate transition was also a period of drastic changes in global atmospheric circulation. The development of the South Asian monsoon is not well understood and mainly derived from proxy records of wind strength. Data for middle Miocene changes in rainfall are virtually non‐existent for India and the Arabian Sea prior to 11 Ma. This study presents planktic foraminiferal trace element (Mg/Ca and Ba/Ca) and stable oxygen isotope records from NGHP‐01 Site 01A off the coast of West India in the Eastern Arabian Sea (EAS) to reconstruct the regional surface hydrography and hydroclimate in the South Asian monsoon (SAM) region during the middle Miocene. The Ba/Ca and local seawater δ18O (δ18Osw) changes reveal a notable gradual increase in SAM rainfall intensity during the middle Miocene. Additionally to this long‐term increase in precipitation, the seawater δ18O is punctuated by a prominent decrease, i.e. freshening, at ~14 Ma contemporary with Antarctic glaciation. This suggests that Southern Ocean Intermediate Waters (SOIW) transmitted Antarctic salinity changes into the Arabian Sea via an "oceanic tunnel" mechanism. The middle Miocene increase in SAM rainfall is consistent with climate model simulations of an overall strengthening Asian monsoon from the Eocene to the middle/late Miocene with a further acceleration after the middle Miocene climate transition. Key Points: We present the first South Asian monsoon (SAM) rainfall record for the Eastern Arabian Sea region for the middle to late MioceneWe find an intensification of SAM rainfall from ~15 to 11 MaIntensification of the SAM is consistent with climate models of an overall strengthening Asian monsoon from the Eocene to late Miocene [ABSTRACT FROM AUTHOR]