West Pacific Research Articles

Evaluating Chinook salmon (Oncorhynchus tshawytscha) response to artificial light in support of bycatch mitigation

In commercial trawl fisheries in the North Pacific and US West Coast, fishermen and scientists are evaluating if artificial lights facilitate escapement of bycaught Chinook salmon (Oncorhynchus tshawytscha) from the trawl by attracting them to an opening provided by a bycatch reduction device. Inconsistent behaviour and escapement rates when lights were used in the trawl led us to conduct a laboratory study to evaluate the role of light properties (intensity, colour, and strobe) on marine Chinook salmon behaviour. Results from this study suggest a negative phototactic response. Light colour and strobe, and the interaction between them, differentially affected behavioural response with regard to mean swimming speed and distance from and habituation to the light. White light intensity had limited influence on response; however, the range of trialed intensities was limited. While behaviour is contextual and responses in a laboratory setting cannot be directly extrapolated to responses in fishing gear, this study highlights the significant role of light properties when trying to affect behaviour for bycatch mitigation and the importance of distinguishing between a response to light and to illuminated surroundings.

Mexctenapseudes boeschi, a new tanaidacean genus and species (Crustacea: Peracarida: Apseudomorpha: Parapseudidae) from the Mexican coast of Campeche with the designation of a new related Australian genus to receive Longiflagrum caeruleus (Boesch, 1973).

Two new genera of parapseudid Tanaidacea belonging to the Discapseudes-Halmyrapseudes Complex sensu Heard et al. (=Complex) are designated from Mexican and Australian waters. Mexctenapseudes boeschi n. gen., n. sp. is described from Campeche Mexico and Pseudolongiflagrum n. gen. is designated from Australia. The new Mexican genus displays similarities to the West Pacific and Indian Ocean genera Ctenapseudes Bamber, Ariyananda Silva, 1997 and Longiflagrum Guu, 1995. The new related genus, Pseudolongiflagrum, having affinities with Ctenapseudes and Mexctenapseudes n. gen., is designated to receive Longiflagrum caeruleus (Boesch) known from Australia. A key to the genera within the parapseudid subfamily Parapseudinae Guu is presented and possible factors concerning the ecology, origins, and distribution of the members of the Complex considered.

Diversity of Pacific Agathotanais (Peracarida: Tanaidacea)

Agathotanaisis one of the seven genera classified into the family Agathotanaidae. So far, 12 species have been described for the genus, seven of which are known from the Pacific. However, considering the present poor state of knowledge on deep-sea environments, a much higher number ofAgathotanaisspecies than currently known can be suspected. Among the studied material, collected from below 1,000 m during five deep-sea expeditions in different parts of the Pacific Ocean, we identified eight species: two of them were already known to the science and five species were identified as new to knowledge and their formal description is presented in the paper: two from the North West Pacific (the Sea of Okhotsk and Kuril-Kamchatka Trench), two from the Central Pacific (Clarion-Clipperton Fracture Zone), and one from the Australian slope. The eighthAgathotanaisspecies in our material was determined using a molecular approach, but it was represented by only one partially destroyed individual and could therefore not be formally described. The proportion ofAgathotanaiscollected at the Sea of Okhotsk was the highest (22%), whereas the numbers were substantially lower for the Kuril-Kamchatka Trench, and the Central and the Southern Pacific. Molecular analyses confirmed the monophyly ofAgathotanaisandParagathotanaisand a close relationship between both genera. Moreover, a close relationship between the two Australian species was revealed. As a result of our findings, the number of species known from the Pacific increased from 5 to 11, with the total number of species in this genus increasing from 12 to 17. An updated identification key forAgathotanaisspecies is given.

Co-Occurrence of HIMU and EM1 Components in a Single Magellan Seamount: Implications for the Formation of West Pacific Seamount Province

ABSTRACT Our general understanding of mantle composition and dynamics mainly comes from the composition of lavas from oceanic intraplate volcanoes. They are generally accepted to originate from deep, relatively stationary mantle plumes. Many groups of seamounts comprising the West Pacific Seamount Province (WPSP), however, do not form long-lived, narrow and continuous chains of volcanoes with clear age progression; thus, their origin does not seem to fit this general model. Here we show a wide compositional spectrum of lavas from the Pako guyot within the Magellan seamount trail (MST), an age-progressive but short-lived volcanic chain in the WPSP. For the first time, both extreme high μ = 238U/204Pb mantle (HIMU)- and enriched mantle 1 (EM1)-like mantle plume components occur in a single seamount in the Pacific Ocean. Based on alteration resistant trace element and Sr–Nd–Pb–Hf isotopic compositions, the Pako lavas fall into three distinct groups. Group 1 has a distinctive HIMU composition with high (206Pb/204Pb)i ratios (20.41–20.94) similar to the Arago (also known as ‘Young Rurutu’ or ‘Atiu’) hotspot composition, suggesting derivation from a HIMU mantle source. Groups 2 and 3 EM1-like lavas comprise the dominant rock type and display the largest Sr–Nd–Pb–Hf isotopic variations that can be best explained by mixing between melts of focal zone (FOZO) and EM1-like mantle components. Additionally, olivine phenocrysts from Group 3 EM1-like lavas have high Ni contents, Fe/Mn and Mn/Zn ratios and low Zn/Fe*10 000 ratios, which can be explained through fractional crystallization of high-pressure partial melts from fertile peridotite. The EM1-like Groups 2 and 3 lavas are compositionally similar to the Rarotonga hotspot composition, suggesting that the MST is possibly an old trace of the Rarotonga hotspot, which is most likely a long-lived hotspot generated above a deep mantle plume. Combined with existing geochemical and tectonic data, we propose that the Magellan seamounts were likely derived from partial melting of a heterogeneous mantle plume containing HIMU, FOZO and EM1-like components. Alternatively, they could have been derived from the Arago and Rarotonga mantle plumes, each having its distinct compositional signature. The occurrence of HIMU- and EM1-like mantle plume components in a single volcano suggests that the superposition of compositionally different hotspot volcanic trails in the South Pacific could have played an important role in the generation of the WPSP.

Search and Rescue in the Pacific West States.

The training practices and the level of medical oversight of search and rescue (SAR) organizations in the US National Park Service (NPS) Pacific west region is not known. A database of SAR teams in the NPS Pacific west region was assembled using public sources. SAR team leaders received an electronic survey between May and December 2019. A descriptive analysis characterizing team size, technical and medical training protocols, and medical oversight was completed. Results are reported as median (interquartile range, range). Of the 250 SAR teams contacted, 39% (n=97) completed our survey. Annual mission volume was 25 (10-50, 1-200). Team size was 30 members (22-58, 1-405). SAR teams most frequently trained in helicopter operations (77%), low-angle rope rescue (75%), and avalanche rescue (43%). Nearly all teams (99%) had members with some medical training: first aid or cardiopulmonary resuscitation (89%), emergency medical technicians (75%), registered nurses or midlevel providers (52%), and physicians (40%). SAR members administered field medical care (84%), often in coordination with EMS (77%). Medical direction was present on a minority of teams (45%), most frequently by a provider specialized in emergency medicine (68%). Expanded medical procedures were permitted on 21% of SAR teams. SAR teams across the NPS Pacific west region had composition and training standards similar to those surveyed previously in the US intermountain states. Healthcare professionals were present on most teams, typically as team members, not as medical directors. Few SAR teams use medical protocols in remote care environments.

Synergistic Effects of PDO and IOD on Water Vapor Transport in the Preflood Season over South China

It is urgent to improve the prediction accuracy of precipitation in the preflood season (PFS) over South China (SC) under the background of global warming, and thus the research of water vapor conditions is the key. For the period of 1960–2012, using the daily precipitation data from 60 meteorology stations in SC and National Centers for Environmental Prediction (NCEP) reanalysis data, the synergistic effect of PDO (the Pacific Decadal Oscillation) &IOD (the Indian Ocean Dipole Mode) on water vapor transport process to frontal/monsoon precipitation is revealed, based on the Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT_4.9). For the frontal precipitation, the positive PDO phase (PDO+) compared with the negative PDO phase (PDO−), there is more water vapor over the West Pacific (WP), the northern South China Sea (SCS), and the Bay of Bengal (BOB). Water vapor for frontal precipitation mainly comes from WP and SCS. When PDO and IOD are in phase resonance, the water vapor transport tracks from the SCS, WP are shorter and westward, so more water vapor is transported to SC, the precipitation efficiency of water vapor to PFS precipitation is higher too. For the summer monsoon precipitation, the tropical Indian Ocean (IO)-BOB is rich in water vapor, especially for PDO−& IOD+. The main water vapor transport tracks are the cross-equatorial flows in the IO, BOB and SCS. The precipitation efficiency of water vapor from the IO-BOB is higher for the positive IOD phase (IOD+) than that for the negative IOD phase (IOD−); however, the precipitation efficiency of water vapor from SCS is higher for the IOD− than that for IOD+. Compared with frontal precipitation, the strong westerly anomaly in the northern IO increases the water vapor transport from the north IO, BOB to SC during monsoon precipitation. For the PDO+&IOD+, the stronger Indian Low and cyclonic anomaly in the WP increases the water vapor transported from the IO-BOB to SC, improving the precipitation efficiency of water vapor. Understanding the synergistic effect of the PDO and IOD on water vapor transport will help to improve the accuracy of precipitation prediction, and reduce the negative impact of drought and flood disasters.

Population Genetic Differentiation on the Hydrothermal Vent Crabs Xenograpsus testudinatus along Depth and Geographical Gradients in the Western Pacific

Connectivity in deep-sea organisms must be considered across both depth gradient and horizontal geographical scales. The depth-differentiation hypothesis suggests that strong environmental gradients (e.g., light, temperature, pressure) and habitat heterogeneity in the deep-sea can create selection pressure, and this can result in genetic population divergence. The hydrothermal vent crab Xenograpsus testudinatus (Xenograpsidae) is common in vents at Kueishan Island, Taiwan, ranging from 10 to about 300 m depths. Xenograpsus testudinatus has also been found in shallow water vents (3–20 m) at Kagoshima and the Izu archipelago of Japan. We examine the sequence divergences in the mitochondrial COI, 16S rRNA and D-loop genes, to test the hypothesis that there is significant genetic differentiation among populations of X. testudinatus along the depth gradient at Kueishan Island (30, 200, 209–224 and 250–275 m), and among different geographical regions (Kueishan, Kagoshima and the Izu archipelago) in the West Pacific. There is neither significant population differentiation among shallow or deep-sea vents, nor between geographical locations. Vertical migration of zoea, upwelling on the eastern coast of Taiwan and the strong effect of the Kuroshio Currents has probably resulted in a high level of planktonic larval dispersal of X. testudinatus along the depth and geographical gradients in the Western Pacific.

Ommastrephid squid paralarvae potential nursery habitat in the tropical-subtropical convergence off Mexico

The Gulf of California and adjacent Pacific have passed through a prolonged warming period that affects the Humboldt squid D. gigas life cycle, which was the third largest fishery in Mexico until its total collapse after 2010. The aims of the present study were (i) to characterize the nursery habitat of paralarvae of the complex Sthenoteuthis oualaniensis–Dosidicus gigas (SD complex) on the basis of 1112 paralarvae collected from zooplankton trawls carried out during ten oceanographic cruises off northwestern Mexico between 2010 and 2017; and (ii) to model the seasonal and interannual variability of the nursery habitat, applying a generalized additive model (GAM) using a regional long-term (1922–2017) hydrographic database. The GAM showed significant relationships of paralarvae abundance with the seasonal average of thermocline depth, absolute salinity, and conservative temperature. The potential nursery habitat of the SD complex paralarvae showed its maximum expected abundance in the entrance of the Gulf of California during spring, when the thermocline depth was shallowest (<30 m). During summer the nursery habitat moved northward along the Pacific west coast of the peninsula. Autumn and winter were less suitable seasons for paralarvae nursery because the thermocline was deep throughout the area of study. Potential nursery habitat did not change interannually in location during La Niña conditions, but did increase the expected abundance in its southern extension. El Niño events contracted the nursery habitat near Cabo San Lucas, and caused the habitat to move northwards over both coasts of the Baja California peninsula. Despite seasonal and interannual climatic variability, two regions remained suitable habitats almost throughout the year. One was associated with coastal upwelling regions (Cabo Corrientes) and the second comprised the oceanic region of high mesoscale kinetic energy located south of Cabo San Lucas. We conclude that the potential nursery habitat of the SD complex is more coastal than oceanic, and is associated with a shallow thermocline in the tropical-subtropical convergence off Mexico. The recent anomalous warming period in this region could drive the changes in the morphology of D. gigas in the Gulf of California, given the effects of environmental variability over early stages of development throughout the adult ontogenesis.

Construction of the Continental Asia in Phanerozoic: A Review

AbstractThis is a review of the formation and tectonic evolution of the continental Asia in Phanerozoic. The continental Asia has formed on the bases of some pre‐Cambrian cratons, such as the Siberia, India, Arabia, North China, Tarim, South China, and Indochina, through multi‐stage plate convergence and collisional collages in Phanerozoic. The north‐central Asia had experienced the expansion and subduction of the Paleo‐Asian Ocean (PAO) in the early Paleozoic and the closure of the PAO in the late Paleozoic and early Mesozoic, forming the PAO regime and Central Asian orogenic belt (CAOB). In the core of the CAOB, the Mongol‐Okhotsk Ocean (MOO) opened with limited expansion in the Early Permian and finally closed in the Late Jurassic–Early Cretaceous. The south‐central Asia had experienced mainly multi‐stage oceanic opening, subduction and collision evolution in the Tethys Ocean, forming the Tethys regime and Himalaya‐Tibetan orogenic belt. In eastern Asia, the plate subduction and continental margin orogeny on western margin of the Pacific Ocean, forms the West Pacific regime and West Pacific orogenic belt. The PAO, Tethys, and West Pacific regimes, together with Precambrian cratons among or surrounding them, made up the major tectonic and dynamic systems of the continental Asia in Phanerozoic. Major tectonic events, such as the Early Paleozoic Qilian, Uralian, and Dunhuang orogeneses, the late Paleozoic East Junggar, Tianshan and West Junggar orogeneses, the Middle to Late Permian Ailaoshan orogeny and North‐South Lhasa collision, the early Mesozoic Indochina‐South China and North‐South China collisions, the late Mesozoic Mongolia‐Okhotsk orogeny, Lhasa‐Qiangtang collision, and intra‐continental Yanshanian orogeny, and the Cenozoic Indo‐Asian, Arab‐Asian, and West Pacific margin collisions, constrained the formation and evolution of the continental Asia. The complex dynamic systems have left large number of deformation features, such as large‐scale strike‐slip faults, thrust‐fold systems and extensional detachments on the continental Asia. Based on past tectonics, a future supercontinent, the Ameurasia, is prospected for the development of the Asia in ca. 250 Myr.

Biogeography and Biodiversity of the Intertidal Barnacle Tetraclita Species in the Gulf of Thailand and Andaman Sea – Influences of Oceanographic Currents and Pleistocene Glaciations

The present study investigated the phylogeography of the intertidal barnacle Tetraclita in the Gulf of Thailand ecoregion (Sunda Shelf Province in the Pacific) and the Andaman Sea Coral Coast ecoregion (Andaman Province in the Indian Ocean) in Thailand’s waters. Tetraclita species were identified by a combined morphological and molecular approach using mitochondrial gene fragments (CO1 and 12S rRNA). Tetraclita singaporensis is a major occupiers on the Andaman coast but is sparse in the western Gulf of Thailand. Tetraclita squamosa inhabits almost all of our collection sites in the Gulf of Thailand but has a very low abundance in the Andaman Sea. Tetraclita kuroshioensis has two genetically distinct populations, one in the Andaman Sea and the other in the West Pacific region. S-DIVA analysis showed that the most recent common ancestor (MRCA) of T. kuroshioensis was distributed in both the Andaman Sea and West Pacific region, with a relative probability of 63%; the analysis further identified two molecular subclades, one on each side of the Sunda Shelf by vicariance about 0.53 million years ago, far before the Last Glacial Maximum (LGM). The MRCA of T. squamosa was based in the West Pacific region (relative probability: 90%), and dispersed into the Andaman Sea after the LGM. The MRCA of T. singaporensis was in the Andaman Sea (relative probability: 89.5%) and dispersed into the Gulf of Thailand via monsoonal currents through the Malacca Strait after the LGM. Presently, T. singaporensis is absent from the West Pacific region, further supporting its origin in the Andaman Sea. The distribution of intertidal barnacles in the Sunda Shelf and Andaman provinces is a result of the interplay between geological events and present day oceanographic currents.

Ecology of Ixodes pacificus Ticks and Associated Pathogens in the Western United States.

Lyme disease is the most important vector-borne disease in the United States and is increasing in incidence and geographic range. In the Pacific west, the western black-legged tick, Ixodes pacificus Cooley and Kohls, 1943 is an important vector of the causative agent of Lyme disease, the spirochete, Borrelia burgdorferi. Ixodes pacificus life cycle is expected to be more than a year long, and all three stages (larva, nymph, and adult) overlap in spring. The optimal habitat consists of forest cover, cooler temperatures, and annual precipitation in the range of 200–500 mm. Therefore, the coastal areas of California, Oregon, and Washington are well suited for these ticks. Immature stages commonly parasitize Western fence lizards (Sceloporus occidentalis) and gray squirrels (Sciurus griseus), while adults often feed on deer mice (Peromyscus maniculatus) and black-tailed deer (Odocoileus h. columbianus). Ixodes pacificus carry several pathogens of human significance, such as Borrelia burgdorferi, Bartonella, and Rickettsiales. These pathogens are maintained in the environment by many hosts, including small mammals, birds, livestock, and domestic animals. Although a great deal of work has been carried out on Ixodes ticks and the pathogens they transmit, understanding I. pacificus ecology outside California still lags. Additionally, the dynamic vector–host–pathogen system means that new factors will continue to arise and shift the epidemiological patterns within specific areas. Here, we review the ecology of I. pacificus and the pathogens this tick is known to carry to identify gaps in our knowledge.

Socioeconomic Disparities in Pancreas Cancer Resection and Survival in the Veterans Health Administration.

Disparities based on socioeconomic factors such as race, ethnicity, marital status, and insurance status are associated with pancreatic cancer resection, but these disparities are usually not observed for survival after resection. It is unknown if there are disparities when patients undergo their treatment in a non-fee-for-service, equal-access healthcare system such as the Veterans Health Administration (VHA). Patients having T1-T3 M0 pancreatic adenocarcinoma diagnosed between 2006 and 2017 were identified from the VHA Corporate Data Warehouse. Socioeconomic, demographic, and tumor variables associated with resection and survival were assessed. In total, 2580 patients with early-stage pancreatic cancer were identified. The resection rate was 36.5%. Surgical resection was independently associated with younger age [odds ratio (OR) 0.94, p<0.001], White race (OR 1.35, p=0.028), married status (OR 1.85, p=0.001), and employment status (retired vs. unemployed, OR 1.41, p=0.008). There were no independent associations with Hispanic ethnicity, geographic region, or Social Deprivation Index. Resection was associated with significantly improved survival (median 21 vs. 8 months, p=0.001). Among resected patients, survival was independently associated with younger age (HR 1.019, p=0.002), geographic region (South vs. Pacific West, HR 0.721, p=0.005), and employment (employed vs. unemployed, HR 0.752, p=0.029). Race, Hispanic ethnicity, marital status, and Social Deprivation Index were not independently associated with survival after resection. Race, marital status, and employment status are independently associated with resection of pancreatic cancer in the VHA, whereas geographic region and employment status are independently associated with survival after resection. Further studies are warranted to determine the basis for these inequities.

Two New Pseudoscorpion Species of the Coastal Genus Garypus L. Koch, 1873 (Garypidae) and an Updated Checklist of the Pseudoscorpiones of Taiwan.

Pseudoscorpions are predatory microarthropods that feed on even smaller animals, such as mites and springtails. While these organisms are generally considered terrestrial and live in the leaf litter or under barks or rocks, some pseudoscorpions live in the intertidal area, including species in the genera Anagarypus, Anchigarypus, and Garypus in the family Garypidae. This study describes two new species of the genus Garypus L. Koch from Southern Taiwan, Garypus wilsoni Lin & Chang sp. nov. and Garypus sanasai Lin, Huang & Chang sp. nov., reviews the pseudoscorpion fauna of Taiwan, and provides an updated checklist of the country. Specimens of the two new species were collected in seashore habitats and their status as new species were supported by both morphology and molecular phylogenetic analysis. Our discovery marks the first new species of pseudoscorpions reported in Taiwan since 1937, as well as the first records of the family Garypidae in Taiwan and of Garypus in East Asia. Moreover, the discovery of these two new species in Taiwan fills the regional distribution gap between Garypus in Thailand and southward and its closely related genus Anchigarypus in South Korea and Japan. The location where Garypus sanasai Lin, Huang & Chang sp. nov. was found also represents the northernmost distribution of the genus Garypus in the West Pacific.

California &amp; Hawai'i Bound: U.S. Settler Colonialism and the Pacific West, 1848-1959 by Henry Knight Lozano (review)

California &amp; Hawai'i Bound: U.S. Settler Colonialism and the Pacific West, 1848-1959 by Henry Knight Lozano (review)

Gender and Geographic Trends Amongst Foot &amp; Ankle Surgeons: Where Are We and Where Do We Need to Improve?

Category:OtherIntroduction/Purpose:Clinical and elective experiences as well as the guidance of mentors are all critical factors in the pursuance of orthopedic residencies and fellowships. Women have historically been underrepresented in orthopedics. Some propose that the root cause lies in the lack of availability in the aforementioned factors. Previous studies demonstrated geographic differences in sex representation in orthopedic residency programs. Studies over geographic distributions of orthopedic foot and ankle (OFA) surgeons showed high variation in geographic density of OFA surgeons throughout the U.S. This study seeks to determine both the gender and geographic distributions of OFA surgeons as well as to determine geographic patterns between their training locations and current practices.Methods:AOFAS data regarding fellowship completion from 1988 through 2021 was analyzed with regards to gender and fellowship location. Internet searches were performed for all those identified within the database for their medical school, residency, and current practice location. This biographical data was obtained from their front-facing biographical webpage or hospital affiliation. States were placed into regions and subsequent divisions as defined according to the US Census Bureau definition: Northeast (New England and Middle Atlantic), Midwest (East North Central and West North Central), South (South Atlantic, East South Central, and West South Central) and West (Mountain and Pacific).Results:1,088 OFA surgeons were analyzed. 168 (15.3%) were female and 922 (84.7%) were male. Female-held OFA fellowship positions increased over time, currently sitting at 13 (22% of all fellowship positions), with a maximum of 15 (25%) in 2017. Geographically, the Pacific had most females (n=26, 15.6% of females), while East South Central had least (n=10, 6.0%). The South Atlantic had most males (n=193, 20.9% of males) while East South Central had least (n=59, 5.3%). The region with the most OFA surgeons in total was the South Atlantic (n=218, 20.0% of the total) whereas the regions with the least were East South Central and New England (n=59, 5.4% in each).Conclusion:Although the amount of female OFA surgeons has increased, the numbers are still low. Geographically, the East South Central division of the U.S consistently had the least number of OFA surgeons whereas the South Atlantic division had the highest.

Taxonomy and phylogeny of the genus Melita (Crustacea: Amphipoda: Melitidae) from the West Pacific Islands, with descriptions of four new species

The amphipod genus MelitaLeach, 1814 (Amphipoda: Melitidae) is a predominantly marine group with a cosmopolitan distribution in both circumtropical and temperate waters. However, records of Melita from inland waters such as fresh and brackish waters are limited. In this study, four new species of Melita are described from inland waters in the Ogasawara and Ryukyu Islands, West Pacific: M. nunomurai sp. nov. from Hahajima Island, Ogasawara Islands; M. ogasawaraensis sp. nov. from Anijima, Chichijima, and Hahajima Islands, Ogasawara Islands; M. miyakoensis sp. nov. from Miyakojima Island, Ryukyu Islands; and M. okinawaensis sp. nov. from Okinawajima Island, Ryukyu Islands. Molecular phylogenetic analyses based on nuclear and mitochondrial DNA sequences reveal that M. ogasawaraensis sp. nov. and M. nunomurai sp. nov. are recovered as the sister taxon of M. miyakoensis sp. nov. and M. choshigawaensis, respectively. These results suggest multiple colonisations of the Ogasawara Islands by Melita species. The present study revealed a high species diversity of Melita in the inland waters of the islands of West Pacific. We further discuss the phylogeny among genera of Melitidae.

Influence of Weather Conditions and Climate Oscillations on the Pine Looper Bupalus piniaria (L.) Outbreaks in the Forest-Steppe of the West Siberian Plain

The pine looper Bupalus piniaria (L.) is one of the most common pests feeding on the Scots pine Pinus sylvestris L. Pine looper outbreaks show a feature of periodicity and have significant ecological and economic impacts. Climate and weather factors play an important role in pine looper outbreak occurrence. We tried to determine what weather conditions precede B. piniaria outbreaks in the southeast of the West Siberian Plain and what climate oscillations cause them. Due to the insufficient duration and incompleteness of documented observations on outbreaks, we used the history of pine looper outbreaks reconstructed using dendrochronological data. Using logistic regression, we found that the factor influencing an outbreak the most is the weather four years before it. A combination of warm spring, dry summer, and cool autumn triggers population growth. Summer weather two years before an outbreak is also critical: humidity higher than the average annual value in summer is favorable for the pine looper. The logistic regression model predicted six out of seven outbreaks that occurred during the period for which weather data are available. We discovered a link between outbreaks and climatic oscillations (mainly for the North Atlantic oscillation, Pacific/North America index, East Atlantic/Western Russia, West Pacific, and Scandinavian patterns). However, outbreak predictions based on the teleconnection patterns turned out to be unreliable. We believe that the complexity of the interaction between large-scale atmospheric processes makes the direct influence of individual oscillations on weather conditions relatively small. Furthermore, climate changes in recent decades modulated atmospheric processes changing the pattern predicting pine looper outbreaks: Autumn became warmer four years before an outbreak, and summer two years before became drier.

Strengthening Southern Hemisphere Westerlies and Amundsen Sea Low Deepening Over the 20th Century Revealed by Proxy‐Data Assimilation

AbstractWinds and pressure over the Southern Ocean are critical to many aspects of the climate system, but the brevity of climate data in this region makes it challenging to interpret recent changes. Here, we reconstruct 20th century sea level pressure and zonal surface wind anomalies over the Southern Ocean, using data assimilation with a global paleoclimate proxy database and four climate‐model priors. The reconstructions agree well with instrumental reanalysis products, especially in the circumpolar westerly and Pacific regions. We observe significant strengthening in the midlatitude Pacific westerlies, associated with a deepening Amundsen Sea Low, throughout the 20th century in all four reconstructions. When the prior includes anthropogenic forcing, we observe poleward‐shifting circumpolar westerlies throughout the 20th century. Our results highlight the combined roles of natural variability and anthropogenic forcing, and the zonally asymmetric character of atmospheric circulation changes at high southern latitudes, with implications for Antarctic ice sheet change.

Soluble Iodine Speciation in Marine Aerosols Across the Indian and Pacific Ocean Basins

Iodine affects the radiative budget and the oxidative capacity of the atmosphere and is consequently involved in important climate feedbacks. A fraction of the iodine emitted by oceans ends up in aerosols, where complex halogen chemistry regulates the recycling of iodine to the gas-phase where it effectively destroys ozone. The iodine speciation and major ion composition of aerosol samples collected during four cruises in the East and West Pacific and Indian Oceans was studied to understand the influences on iodine’s gas-aerosol phase recycling. A significant inverse relationship exists between iodide (I–) and iodate (IO3–) proportions in both fine and coarse mode aerosols, with a relatively constant soluble organic iodine (SOI) fraction of 19.8% (median) for fine and coarse mode samples of all cruises combined. Consistent with previous work on the Atlantic Ocean, this work further provides observational support that IO3– reduction is attributed to aerosol acidity, which is associated to smaller aerosol particles and air masses that have been influenced by anthropogenic emissions. Significant correlations are found between SOI and I–, which supports hypotheses that SOI may be a source for I–. This data contributes to a growing observational dataset on aerosol iodine speciation and provides evidence for relatively constant proportions of iodine species in unpolluted marine aerosols. Future development in our understanding of iodine speciation depends on aerosol pH measurements and unravelling the complex composition of SOI in aerosols.

Is Hodgkin Lymphoma Associated with Hepatitis B and C Viruses? A Systematic Review and Meta-analysis.

Apart from the Epstein-Barr virus (EBV), the etiology of the hematologic malignancy Hodgkin lymphoma (HL) is not well defined. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are associated with some lymphoproliferative diseases with similarities to HL. We performed a systematic review and meta-analysis, by searching Embase, MEDLINE, and Web of Science databases on March 9, 2021, for studies reporting a measure of association for HBV and HL or HCV and HL. We calculated pooled relative risks (RR) and their 95% confidence intervals (CI). Pooling nine HBV studies with 1,762 HL cases yielded an RR of 1.39 (95% CI, 1.00-1.94) and pooling 15 HCV studies with 4,837 HL cases resulted in an RR of 1.09 (95% CI, 0.88-1.35). Meta-analyzing by study design, hepatitis detection method, and region revealed two subgroups with statistically significant associations-HCV studies that used hospital-based controls and/or were conducted in the West Pacific. No included study assessed age or EBV tumor status in relation to HL. Although we did not find an association between HBV or HCV and HL, research assessing the impact of age and EBV tumor status was lacking. The effect of HBV or HCV infection in the development of HL remains unclear.