A Comparison of Global Estimates of Marine Primary Production From Ocean Color

The third primary production algorithm round robin (PPARR3) compares output from 24 models that estimate depth-integrated primary production from satellite measurements of ocean color, as well as seven general circulation models (GCMs) coupled with ecosystem or biogeochemical models. Here we compare the global primary production fields corresponding to eight months of 1998 and 1999 as estimated from common input fields of photosynthetically-available radiation (PAR), sea-surface temperature (SST), mixed-layer depth, and chlorophyll concentration. We also quantify the sensitivity of the ocean-color-based models to perturbations in their input variables. The pair-wise correlation between ocean-color models was used to cluster them into groups or related output, which reflect the regions and environmental conditions under which they respond differently. The groups do not follow model complexity with regards to wavelength or depth dependence, though they are related to the manner in which temperature is used to parameterize photosynthesis. Global average PP varies by a factor of two between models. The models diverged the most for the Southern Ocean, SST under 10 degrees C, and chlorophyll concentration exceeding 1 mg Chl m-3. Based on the conditions under which the model results diverge most, we conclude that current ocean-color-based models are challenged by high-nutrient low-chlorophyll conditions, and extreme temperatures or chlorophyll concentrations. The GCM-based models predict comparable primary production to those based on ocean color: they estimate higher values in the Southern Ocean, at low SST, and in the equatorial band, while they estimate lower values in eutrophic regions (probably because the area of high chlorophyll concentrations is smaller in the GCMs). Further progress in primary production modeling requires improved understanding of the effect of temperature on photosynthesis and better parameterization of the maximum photosynthetic rate

Biochemical properties of warm eddies reproduced by western Arctic marine ecosystem model

第2回極域科学シンポジウム/第34回気水圏シンポジウム 11月17日（木） 統計数理研究所 セミナー室

Seafloor survey of Nishinoshima Island using an Autonomous Underwater Vehicle

東京都小笠原諸島の無人の火山島である西之島は、2020年の大規模な噴火により陸上部分は溶岩や火山灰に覆われたことが明らかになっている一方、海中部分については調査が進んでおらず、溶岩や火山灰がどの程度まで広がっているか、また魚類や底生生物等がどのような状況になっているのか明らかでなかった。そこで、2021年7月、低コスト自律型海中ロボットシステムを用いて海中および海底の画像観測を実施した。強い潮流下での調査であったが、急峻な地形を含む海底の詳細な光学画像撮影に成功した。西之島北部の海底において火山灰が降り積もる平坦な地形が確認された。北東部の海底においては噴気が確認された。また、サメ等の大型魚から小型魚、タコ等の複数の遊泳生物が確認された。Nishinoshima Island is an uninhabited volcanic island in the Ogasawara Islands of Tokyo. While it is clear that the terrestrial part of the island was covered with lava and volcanic ash due to a large-scale eruption in 2020, the underwater part had not been surveyed yet, and it was unclear how far the lava and volcanic ash have spread and what the situation is for fish and benthic organisms. In July 2021, underwater and seafloor observations were carried out using a low-cost autonomous underwater vehicle system. Despite the strong currents, we succeeded in taking detailed optical images of the seafloor, including the steep topography. Volcanic ash was deposited on the seafloor in the northern part of Nishinoshima Island, and flat topography was observed. In the northeastern part of the seafloor, the fume emission was observed. In addition, several kinds of nektons, from large fish such as sharks to small fish and an octopus, were captured on HATTORI’s camera.departmental bulletin pape

Drivers and uncertainties of future global marine primary production in marine ecosystem models

Past model studies have projected a global decrease in marine net primary production (NPP) over the 21st century, but these studies focused on the multi-model mean rather than on the large inter-model differences. Here, we analyze model-simulated changes in NPP for the 21st century under IPCC's high-emission scenario RCP8.5. We use a suite of nine coupled carbon–climate Earth system models with embedded marine ecosystem models and focus on the spread between the different models and the underlying reasons. Globally, NPP decreases in five out of the nine models over the course of the 21st century, while three show no significant trend and one even simulates an increase. The largest model spread occurs in the low latitudes (between 30° S and 30° N), with individual models simulating relative changes between −25 and +40 %. Of the seven models diagnosing a net decrease in NPP in the low latitudes, only three simulate this to be a consequence of the classical interpretation, i.e., a stronger nutrient limitation due to increased stratification leading to reduced phytoplankton growth. In the other four, warming-induced increases in phytoplankton growth outbalance the stronger nutrient limitation. However, temperature-driven increases in grazing and other loss processes cause a net decrease in phytoplankton biomass and reduce NPP despite higher growth rates. One model projects a strong increase in NPP in the low latitudes, caused by an intensification of the microbial loop, while NPP in the remaining model changes by less than 0.5 %. While models consistently project increases NPP in the Southern Ocean, the regional inter-model range is also very substantial. In most models, this increase in NPP is driven by temperature, but it is also modulated by changes in light, macronutrients and iron as well as grazing. Overall, current projections of future changes in global marine NPP are subject to large uncertainties and necessitate a dedicated and sustained effort to improve the models and the concepts and data that guide their developmen

Current Performance and On-Going Improvements of the 8.2 m Subaru Telescope

An overview of the current status of the 8.2 m Subaru Telescope constructed and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of Japan is presented. The basic design concept and the verified performance of the telescope system are described. Also given are the status of the instrument package offered to the astronomical community, the status of operation, and some of the future plans. The status of the telescope reported in a number of SPIE papers as of the summer of 2002 are incorporated with some updates included as of 2004 February. However, readers are encouraged to check the most updated status of the telescope through the home page, http://subarutelescope.org/index.html, and/or the direct contact with the observatory staff.Comment: 18 pages (17 pages in published version), 29 figures (GIF format), This is the version before the galley proo

Radiological prediction of tumor invasiveness of lung adenocarcinoma on thin-section CT

To evaluate thin-section computed tomography (CT) (TSCT) features that differentiate adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IVA), and to determine the size of solid portion on CT that correlates to pathological invasive components. Forty-eight patients were included. Nodules were classified into ground-glass nodule (GGN), part-solid, solid, and heterogeneous. Visual density of GGNs was subjectively evaluated using reference standard images: faint GGN (Ga), −400 HU; and mixed (Ga + Gb, Ga + Gc, and Gb + Gc). The evaluated TSCT findings included margin of nodule, distribution of solid portion, distribution of air bronchiologram, and pleural indentation. The longest diameters of the solid portion and the entire tumor were measured. Invasive diameters were measured in pathological specimens. Twenty-two AISs (16 GGNs [7 Ga, 5 Gb, 2 Gc, 1 Ga + Gc, 1 Gb + Gc], 4 part-solids, and 2 heterogeneous), 6 MIAs (1 GGN [Gb + Gc], 3 part-solids, and 2 solids), and 20 IVAs (1 GGN [Gb], 3 part-solids, and 16 solid) were found. The longest diameter (mean ± standard deviation) of the solid portion and total tumor were 9.7 ± 9.7 and 18.9 ± 5.6 mm, respectively. Significant differences in TSCT findings between AIS and IVA were margin of nodule (Pearson chi-squared test, P = 0.004), distribution of air bronchiologram (P = 0.0148), and pleural indentation (P = 0.0067). A solid portion >5.3 mm on TSCT indicated MIA or IVA, and >7.3 mm indicated IVA (receiver operating characteristic analysis, P 7.3 mm on TSCT indicates IVA

Lung interstitial cells during alveolarization

Recent progress in neonatal medicine has enabled survival of many extremely low-birth-weight infants. Prenatal steroids, surfactants, and non-invasive ventilation have helped reduce the incidence of the classical form of bronchopulmonary dysplasia characterized by marked fibrosis and emphysema. However, a new form of bronchopulmonary dysplasia marked by arrest of alveolarization remains a complication in the postnatal course of extremely low-birth-weight infants. To better understand this challenging complication, detailed alveolarization mechanisms should be delineated. Proper alveolarization involves the temporal and spatial coordination of a number of cells, mediators, and genes. Cross-talk between the mesenchyme and the epithelium through soluble and diffusible factors are key processes of alveolarization. Lung interstitial cells derived from the mesenchyme play a crucial role in alveolarization. Peak alveolar formation coincides with intense lung interstitial cell proliferation. Myofibroblasts are essential for secondary septation, a critical process of alveolarization, and localize to the front lines of alveologenesis. The differentiation and migration of myofibroblasts are strictly controlled by various mediators and genes. Disruption of this finely controlled mechanism leads to abnormal alveolarization. Since arrest in alveolarization is a hallmark of a new form of bronchopulmonary dysplasia, knowledge regarding the role of lung interstitial cells during alveolarization and their control mechanism will enable us to find more specific therapeutic strategies for bronchopulmonary dysplasia. In this review, the role of lung interstitial cells during alveolarization and control mechanisms of their differentiation and migration will be discussed