Japan In Winter Research Articles

Lesser White-Fronted GooseAnser erythropusat Sarobetsu in Northern Hokkaido, Japan: A Preliminary Report on Numbers in Autumn

Abstract Lesser White-fronted Goose Anser erythropus is recognized as a globally threatened species. Very small numbers stage and winter in Japan, mostly individually, as families or sometimes in small flocks. Since beginning to observe this species in 2001 at Sarobetsu, northern Hokkaido, Japan, we have noted increasing numbers. The increase, from a few individuals (2001–2004) to flocks (2005–2007), is of interest, given the threatened status of this species. Lesser White-fronted Goose now regularly migrates through Sarobetsu, giving us opportunities to observe this relatively rare winter visitor to Japan. In order to help clarify the status of this threatened species in Japan, we describe and discuss the change in numbers, the proportion of juveniles in flocks, family size and length of stay.

Size Distributions of Polycyclic Aromatic Hydrocarbons in the Atmosphere and Estimation of the Contribution of Ultrafine Particles to Their Lung Deposition

This is the first estimation of the contribution of ultrafine particles to the lung deposition of particle-bound polycyclic aromatic hydrocarbons (PAHs) in the atmosphere. The size distributions of nine PAHs (4-6 rings) were measured at roadside and suburban sites in winter in Japan. Deposition efficiencies and fluxes of PAHs in ultrafine mode (<0.12 microm), accumulation mode (0.12-2.1 microm), and coarse mode (>2.1 microm) to the human respiratory tract were calculated using the LUDEP computer-based model. From 10%-15% and 4.2%-6.9% of target PAHs were distributed in the ultrafine mode in the roadside and suburban atmosphere, respectively. The model calculations showed that as much as 18%-19% and 16%-17% of inhaled PAHs are deposited in the alveolar region of the lung for the roadside and suburban atmosphere, respectively. Total deposition fluxes of target PAHs in the alveolar region were about 1.5-fold greater for the roadside atmosphere than for the suburban atmosphere. Importantly, ultrafine particles were shown to contribute as much as 23%-30% and 10%-16% to PAH deposition in the alveolar region for the roadside and suburban atmosphere, respectively, although the contributions of ultrafine particles to the total particulate matter masswere only 2.3% in the roadside atmosphere and 1.3% in the suburban atmosphere. These results indicated that ultrafine particles are significant contributors to the deposition of PAHs into the alveolar region of the lung.

Remote response of the East Asian winter monsoon to tropical forcing related to El Niño–Southern Oscillation

The mechanism of the East Asian winter monsoon variability in response to El Niño−Southern Oscillation (ENSO)‐related tropical forcing is investigated using Japanese long‐term reanalysis project data, additionally aided by the Japan Meteorological Agency climate data assimilation system. There are at least two different responses, zonally symmetric and asymmetric, of the Asian jet over South Asia to the ENSO‐related tropical convective forcing during the Northern Hemisphere winter. The zonally symmetric response, induced by zonally extended anomalous convection from the Philippine Sea through southern India and Sri Lanka, is pronounced at the mature phase of ENSO. The zonally asymmetric response is intimately associated with anomalous convection localized in the vicinity of the Philippine and South China seas, accompanied by an anomalous Walker circulation cell between the Maritime Continent and tropical Indian Ocean. When this asymmetric response is prominent, ENSO‐related anomalous convection can give rise to a change in the East Asian winter monsoon system through stationary Rossby wave propagation along the South Asian waveguide. The North Atlantic Oscillation (NAO)‐related extratropical forcing is also a crucial factor and contributes not only to the downstream development of subpolar teleconnections across northern Eurasia but also to the reinforcement of the zonally asymmetric pattern of the Asian jet over South Asia, resulting in a significant effect on the East Asian winter monsoon circulation. A combination of the ENSO‐ and NAO‐related forcing plays a vital role in triggering the occurrence of extraordinary anomalous monsoon circulations, such as extremely heavy snowfall in the 2005/2006 winter in Japan.

Epidemiologic Study of Influenza Infection in Okinawa, Japan, from 2001 to 2007: Changing Patterns of Seasonality and Prevalence of Amantadine-Resistant Influenza A Virus

To clarify seasonal influenza patterns and the prevalence of amantadine-resistant influenza A viruses in Okinawa, located at the southern extremity of Japan in a subtropical climate, we conducted a laboratory-based study of influenza virus infections from 2001 to 2007. The annual outbreaks tended to show two peaks in Okinawa, in summer and winter, although the main islands of Japan, located in a temperate climate area, showed only winter influenza activity. Epidemic types and subtypes in Okinawa mostly matched those on the main islands of Japan in winter and those in Taiwan in summer. Rates of amantadine resistance dramatically increased, from 7.3% in the November 2002-to-March 2003 season to 90.0% in summer 2005, and a similarly high rate of resistance continued for the rest of the study period. Phylogenetic analysis of the hemagglutinin gene of A/H3N2 isolates collected from 2002 to 2007 revealed a monophyletic lineage that was divided into four period groups. Each group included amantadine-sensitive and -resistant viruses within independent clusters. In the November 2005-to-March 2006 season, all of the amantadine-resistant viruses were clustered in clade N, with dual (position 193 and 225) amino acid mutations in their HA1 subunits. In 2005, clade N amantadine-resistant viruses existed in Okinawa several months before the circulation of this clade on the main islands of Japan. In conclusion, surveillance in Okinawa to monitor influenza virus circulation is important for elucidating the dynamics of virus transmission in a border area between temperate and subtropical areas, as Okinawa is one of the best sentinel points in Japan.

Breeding-Season Sympatry Facilitates Genetic Exchange Among Allopatric Wintering Populations of Northern Pintails in Japan and California

Abstract. The global redistribution of pathogens, such as highly pathogenic avian influenza, has renewed interest in the connectivity of continental populations of birds. Populations of the Northern Pintail (Anas acuta) wintering in Japan and California are considered separate from a management perspective. We used data from band recoveries and population genetics to assess the degree of biological independence of these wintering populations. Distributions of recoveries in Russia of Northern Pintails originally banded during winter in North America overlapped with distributions of Northern Pintails banded during winter in Japan. Thus these allopatric wintering populations are partially sympatric during the breeding season. The primary areas of overlap were along the Chukotka and Kamchatka peninsulas in Russia. Furthermore, band recoveries demonstrated dispersal of individuals between wintering populations both from North America to Japan and vice versa. Genetic analyses of samples from both wintering popu...

Evaluation of Lightning Fault Rate of Transmission Line on the Coastal Area of the Sea of Japan in Winter

Spatial distribution of lightning discharges that were observed simultaneously with faults of power transmission lines in Hokuriku area in winter is analyzed. Spatial distribution of all lightning discharges located by LLS in winter around the coastline of the Sea of Japan is analyzed as well for comparison. Majority of the transmission line faults experienced within about 20km from the coastline were associated with positive flashes. On the contrary, most of the faults located inland farther than about 20km from the coastline were associated with negative upward flashes. Distribution of located lightning flashes dependent on their polarities observed by LLS coincides with this pattern of lightning faults. Accordingly, the relationship between the lightning flash density observed by LLS and the frequencies of lightning hits on high structures in winter is examined. Based on this result, the lightning fault rate of 500kV transmission lines in winter is evaluated by using this relationship, resulting in successful reproduction of the high fault rate experienced so far.

Negative Effects of Low Temperatures on the Vertical Transmission and Infection Density of a Spiroplasma Endosymbiont in Drosophila hydei

Maternally transmitted endosymbionts of the genus Spiroplasma infecting several species of Drosophila are known to cause selective death of male offspring (male killing). The male-killing trait is considered to be advantageous for maternally transmitted endosymbionts. However, a non-male-killing spiroplasma is present in Japanese populations of Drosophila hydei at high frequencies (23-66%). This spiroplasma is phylogenetically closely related to the male-killing spiroplasma infecting other Drosophila species. It is unknown why this spiroplasma is maintained in its host populations despite its inability to cause male killing. We examined the susceptibilities of the spiroplasma in D. hydei to four different temperatures (28, 25, 18, and 15 degrees C). Diagnostic PCR revealed that vertical transmission of the spiroplasma was nearly perfect at 28 and 25 degrees C, partially suppressed at 18 degrees C, and completely blocked at 15 degrees C. Furthermore, quantitative PCR demonstrated that offspring treated at 18 degrees C exhibited dramatically lower densities of spiroplasma (i.e., approximately one-tenth) compared to offspring treated at 28 and 25 degrees C. Considering the low temperatures during winter in Japan, some unknown advantageous effects of the spiroplasma that compensate for the failure of vertical transmission are suggested to act in natural populations of D. hydei.

Computer simulations on the initiation and morphological difference of Japan winter and summer sprites

Two‐dimensional (axisymmetric) computer simulations (electromagnetic code) have been performed to study the initiation and morphological difference (summer, carrots, and winter, columns) of sprites for simulating Japan summer and winter sprites. By changing the physical parameters of a parent lightning, we have found the following findings by looking at the spatial‐temporal distribution of reduced electric field, etc. (1) There are three important factors (the height where the charge is removed (ds), charge transfer (Q), and lightning current risetime (τ)) in the initiation of sprites and their morphological differences. (2) For the initiation of sprites, the charge transfer (Q) should exceed a certain value for possible charge heights (giving us a threshold of charge moment change (Qds) of the order of ∼120–200 C·km), with a combination of small risetime of lightning current waveform. (3) Further, the height for positive charge is much higher than that for negative charge in a typical lightning configuration, which is the essential factor in determining the morphological difference of sprites in summer and winter. Positive charges for summer are located at a much higher altitude than those in winter in Japan, which might result in carrot‐type in summer and columnar‐type in winter even for the same positive polarity. (4) A combinational effect of (Ids) and (Qds) is important for having sprites. Finally, the present computer results on the initiation of sprites for Japanese lightning have been compared extensively to the well‐documented properties of summer continental sprites and future subjects to study have been suggested.

広域一斉積雪断面観測による平成１８年豪雪における積雪の地域特性の研究

平成18年豪雪における積雪の地域特性を明らかにすることを目的として,日本各地の雪氷研究者の協力を得て広域―斉積雪断面観測を2006年2月(上旬及び下旬)に2回実施した.観測地点数は,2月上旬の観測では北海道から中国地方にいたる46地点,2月下旬の観測では北海道から北陸地方にいたる26地点である.観測の結果,平成18年豪雪では,全国的にみた場合,融解凍結が関与するざらめ雪化の進行度合に雪質の地域的差異が最も明瞭に表れており,ざらめ率(積雪深に対するざらめ雪層の厚さの割合)は緯度と標高に強く依存して変化していた.また,積雪全層の平均密度と平均硬度には,2月上旬では低緯度ほど大きい傾向があったが,2月下旬になると平均硬度には顕著な南北差は認められなかった.豪雪地域(山間部)の住民から「今年は雪が硬い」という声が多数聞かれたことに対し,新潟県十日町市におけるラム硬度の観測データを用いて検証した結果,2006年2月上旬と下旬の十日町市の平均ラム硬度は1987年以降では群を抜いて大きいことが分かった.過去の豪雪年のラム硬度との比較から,平成18年豪雪における新潟県山間部の積雪硬度の著しい増加は,豪雪年の特徴であると考えられる.

A survey on thermal conditions of bathrooms during winter in Japan

A survey on thermal conditions of bathrooms during winter in Japan

Intensive Field Survey of Aerosol and Gas Concentrations with 6-h Interval Sampling in Winter in Japan

We intensively surveyed the concentrations of chemical species in aerosols and gases using a four-stage filter-pack method at a site in Japan facing the Sea of Japan in winter with 6-h sample intervals. A few chloride species emitted anthropogenically were detected, and the HCl (g) concentration was quite low. The number of chloride species artifacts was also low. The HNO3 (g) concentration was significantly higher when the monitored air mass passed over the Korean Peninsula compared to when it did not pass over the Korean Peninsula. In addition, the HNO3 (g) concentration was significantly higher when the air mass arrived at the monitoring site by passing the route at lower latitude than the latitude of the monitoring site. On the other hand, the SO2 (g) concentration showed no change between various trajectories of the air mass. The $$ {\text{NH}}^{ + }_{4} $$ (p)/non-seasalt- (nss-) $$ {\text{SO}}^{{2 - }}_{4} $$ (p) ratio was intermediate between the compositions of (NH4)2SO4 and NH4HSO4 when the air mass passed over the Korean Peninsula, whereas it was intermediate between NH4HSO4 and H2SO4 when the air mass did not pass over the Korean Peninsula. We detected the transboundary transport of sulfur dioxide with high time-resolution monitoring at two separate monitoring points: the current monitoring site and Oki Island.

Field Survey of Trans-boundary Air Pollution with High Time Resolution at Coastal Sites on the Sea of Japan during Winter in Japan}

An intensive field survey, with 6-h measurement intervals, of concentrations of chemical species in particulate matter and gaseous compounds was carried out at coastal sites on the Sea of Japan during winter. The concentration variation of SO(2)(g) and HNO(3)(g) were well correlated, whereas the NH(3)(g) concentration variation had no correlation with those of SO(2)(g) and HNO(3)(g). The NH(4) (+) (p)/non-sea-salt- (nss-)SO(4) (2 -)(p) ratio in particulate matter was mainly affected by the location of the sampling site. One or more concentration peaks of nss-Ca(2 +) for survey period were observed. Backward trajectories analyses for the highest nss-Ca(2 +) concentration peaks showed some inconsistency in pathways. We consider that insufficient mixing of the atmosphere and/or insufficient time for the transported air pollutants to react with those discharged locally are the most likely explanations for the discrepancies between the measured products [HNO(3)][NH(3)] and the calculated values.

Japanese Democratization and the Little House Books: The Relation between General Head Quarters and The Long Winter in Japan after World War II

Japanese Democratization and the Little House Books:The Relation between General Head Quarters and The Long Winter in Japan after World War II Noriko Suzuki (bio) In 1949, one of the Little House books written by Laura Ingalls Wilder (1867–1957) was introduced in Japan, then under American occupation after World War II. All publishing materials were strictly examined, censored, and revised by General Head Quarters (GHQ), with General Douglas MacArthur (1880–1964) as Supreme Commander for the Allied Powers (SCAP). The Long Winter (1943), the sixth volume of the Little House series, was the first to be granted permission for translation and publication. Upon publication in 1949, the book gained widespread popularity among Japanese readers as GHQ actively encouraged the book's publication and distribution to libraries, including public, school, and new libraries that GHQ established in major cities throughout Japan. Two other books of the Little House series, The Little House in the Big Woods and The Little House on the Prairie, followed The Long Winter in 1950, but they did not achieve as much popularity as The Long Winter did. This little-known episode raises a number of questions. Why did GHQ encourage Japanese schoolchildren to read The Long Winter? Although it was the sixth in the series, why was The Long Winter the first to be translated and published in postwar Japan? Moreover, the cardinal questions that this article pursues are: How did The Long Winter help create the image of the American West in the minds of Japanese readers? How did Japanese people come to accept the book—a memoir of the American frontier? And how did the story of an American woman's frontier life affect the process of Japanese democratization under American occupation after World War II?1 GHQ's major aim of its social reform of Japan was "the removal of all militarism and ultranationalism" and establishment of "a democratic Japan" based on American democratic principles (GHQ, Education 136). To achieve this aim, GHQ issued a wide range of policy directives to the Japanese Imperial Government. Although demobilizing the Japanese Army and the Imperial Navy was the initial purpose of the Allied Powers' occupation, their occupation policy [End Page 65] significantly shifted focus to the social reform of Japan when demilitarization was completed so as to convert Japan into a democratic nation. As a matter of fact, both GHQ and the U.S. government considered the social reform to be a crucial underpinning of reshaping Japan. General MacArthur clearly stated that his occupation policy of Japan was designed "to build a future for the people of Japan based upon considerations of realism and justice" and "to infuse into the hearts and minds of the Japanese people principles of liberty and right heretofore unknown to them;" "[W]ith those very principles . . . we [Americans] become architects of a new Japan" (Whan 165). As MacArthur saw it, social reform in Japan had to entail "reshaping of national and individual character" because such "structural and spiritual changes" were "essential to form the strong foundation of popular support upon which a democratic state must rest."2 To implement social reform effectively, GHQ actively used media as an educational apparatus. In fact, as historian Takeshi Tanigawa remarks, GHQ tried to make the best of any kind of media source—books, textbooks, periodicals, films, radios, and school libraries—to educate Japanese people and accelerate educational reform (58). GHQ's Civil Information and Education Section (CIE),3 for instance, distributed free projectors and films made by the U.S. State Department to local halls, libraries, and schools in 1948. Through this program, 1,084 projectors were distributed, and over 400 educational films were watched by Japanese civilians of all ages (Nakamura). The distributed CIE films were virtually all about the democratic (that is, American) nation that Japan was going to become (Tanigawa 186).4 Besides films, GHQ also took advantage of radio broadcasting in Japan. In the 1940s radio was the major medium for the Japanese people, though the Japanese broadcasting system was severely damaged during the war. It was on the radio that Japanese people first heard the emperor's official announcement of Japan's defeat and surrender. GHQ...

Transport pathways of microphytobenthos-originating organic carbon in the food web of an exposed hard bottom shore in the Seto Inland Sea, Japan

Benthic microalgal production has been clarified to be comparable to water column pro- duction in coastal shallow water ecosystems. The present study examined carbon transport pathways from microphytobenthos to predators in a food web of an exposed hard bottom shore in the Seto Inland Sea of Japan in winter, noting the intermediary role of suspension feeders in the carbon trans- port. Natural abundances of carbon and nitrogen stable isotopes were examined for epilithic organic matter (EOM), suspended particulate organic matter (SPOM), a macroalga, molluscs, crustaceans and fish. All the heterotrophs, including herbivores, suspension feeders and carnivores, showed high δ 13 C signatures of -15.5 to -9.7‰, relative to the δ 13 C of -20.7 to -19.7‰ for the SPOM collected from the offshore surface water as an indicator of phytoplankton. At the shoreline point, the SPOM showed high δ 13 C values of -16.0 to -13.0‰, overlapping with the values of -15.4 to -12.6‰ for the EOM indicative of microphytobenthos collected at the low sea level points, and abundantly included microalgae of the same species found in the epilithic matter. It was thus considered that resuspension of 13 C-enriched microphytobenthos increased the δ 13 C of SPOM in the surf zone and consequently increased the δ 13 C of the suspension feeders through their feeding on the suspended matter. The δ 15 N of carnivores, which overlapped in δ 13 C with these primary consumers, markedly increased with the trophic position. These results indicate that, not only grazing, but also suspension feeding functioned as transport pathways of the 13 C-enriched microphytobenthos in the food web.

The Multi-scale Structure and Development Mechanism of Mesoscale Cyclones over the Sea of Japan in Winter

The western Sea of Japan is a region in which mesoscale cyclones are frequently observed as cold polar air breaks out over the sea. In this region, mesoscale cyclones occasionally develop along a convergence zone that forms on the lee side of the mountains north of the Korean Peninsula. A meso-a-scale cyclone (MaC), in which two meso-b-scale cyclones (MbCs) were embedded, was observed in the western Sea of Japan on 23 January 1990. This structure is referred to as a ‘‘multi-scale structure’’ of a mesoscale cyclone. A simulation experiment and a number of sensitivity experiments with respect to several forcing factors were performed to elucidate the development mechanism of mesoscale cyclones. Stably stratified air flows around the mountains north of the Korean Peninsula and the convergence zone forms on the lee side of the mountains. Large amounts of sensible heat and latent heat are supplied from the sea to the atmosphere. The diabatic heating due to condensation and vertical diffusion of the sensible heat and horizontal advection of the potential temperature y are almost in balance with the negative vertical advection of y. This results in an intense upward motion in the convergence zone. Since baroclinicity is intense in this region, an upward transfer of the horizontal momentum around the convergence zone intensifies the upper-level (800@600 hPa) divergence. Consequently, the surface pressure decreases, and the MaC develops. The upward motion and vorticity are concentrated mostly in the MbCs, which are considered to be the cores of the MaC. On the other hand, the MaC provides an environment for the formation and development of the MbCs and affects their movements.

Lipids and ecdysteroids on the ovarian growth of the adult blow fly, Aldrichina Grahami (Aldrich)

Arrest of oogenesis in Aldrichina grahami (Aldrich) was induced by long days (16L : 8D) at 20℃ and the follicle remained undeveloped in the previtellogenic stage. Ovarian development takes place under short days (11L : 13D) at 20℃ and oviposition occurs 6 days after the adult emergence. Ecdysteroid content in the whole body was measured from adult emergence to day 6 after emergence and the maximum value of ecdysteroid (l,400pg) was detected in the non-diapausing female on day 4, when the uptake of yolk protein by the oocytes began. Lipid content of the ovary and the fat body were compared between females reared under short and long days. The main fatty acids were palmitic, palmitoleic, oleic and linoleic acid. Especially, the content of palmitoleic acid increased from 15 to 40%in the ovary and 23 to 41% in the fat body of the non-diapausing female within 6 days. The high content of palmitoleic acid which has a melting point of ±0.5℃, is assumed to enable A. grahami to undergo alternation of generations at the low environmental temperatures of the winter in Japan.

Activities of sprites and elves in the winter season, Japan

Sprites and elves observation has been carried out in three winter seasons in Japan since December 1998. Thirtyfive sprites’ features have been imaged with CCD cameras and 95 optical emission from elves have been captured with hi-speed array photometers. The number of events observed on a night is dependent on the occurrence of intense cloud to ground lightning activity and cloud condition above the observation site. Most of the sprites/elves are directly associated with storms produced by a cold front passing over Japan. It is found that sprites/elves appear not only in the west coast of Japan but also above the Pacific Ocean. The average vertical length of winter sprites in the west cost is shorter than that of summer sprites in the US by about a factor of 2. The altitude of the causative thunderstorm for winter sprites and elves is comparatively lower than that of the summer events in the US and the horizontal width of the cloud is sometimes smaller than 30 km . The sprites’ detection in winter in Japan suggests the possibility of winter sprite occurrence in Scandinavia and/or Israel where the climate condition is similar to Japan.

Shell Eggs and Salmonella Enteritidis in Various Seasons in Japan.

We investigated the resistance of shell eggs stored under various conditions of temperature and storage periods in summer, autumn and winter in Japan to the growth of Salmonella Enteritidis (SE). SE (5-20 cells/egg) was inoculated at a point in the egg white near the egg yolk. In autumn and winter, stored shell eggs were more resistant to the growth of inoculated SE. Shell eggs inoculated with SE on d 0 of storage in these three seasons showed slight growth of SE at a high frequency. These results showed the necessity of controlling shell egg temperature and storage period in all seasons.

Clinical guidelines to manage malnutrition in nursing homes

Individual aerosol particles collected by a two-stage impactor on Mt. Hotaka (2165 m altitude) in central Japan in winter are studied using a transmission electron microscope and an energy-dispersive X-ray (EDX) analyzer. The size, morphology, elemental composition, mixing state and relative abundances are examined for (~ 550 ) aerosol particles with sizes of 0.1–2.0 μm collected during winter monsoon. Further smaller fine-ultrafine (~ 920) particles with sizes of 0.02–0.5 μm are also studied by electron-beam bombardment. There are potassium-containing sulfur particles, which may be originated from biomass burning or biofuel combustion in the Asian continent; sulfur would accumulate on these particles during their transport. Mineral particles and soot-containing particles constitute the minor abundance (less than 10% of all the particles). The samples collected during snowfall contain a very high fraction (> 90%) of fine sulfur-rich particles and no coarse particles are collected; precipitation may scavenge these coarse particles from the atmosphere. The electron-beam bombardment analysis reveals that the most abundant particles are the electron-beam sensitive (damaged) particles, which account for 70–90% of the total particles. On the basis of the comparison of fine particles with the diameter ranges of 0.1–0.5 μm obtained by both the EDX analysis and electron-beam bombardment analysis, the electron-beam sensitivity/insensitive particles would correspond to sulfur-containing particles/soot or mineral particles although we cannot deny out other particles such as nitrate, organics.

Lightning occurrence data observed with lightning location systems in Japan: 1992-1995

Cloud-to-ground lightning occurrence for years 1992-1995 has been analyzed using the data obtained with nine different lightning location systems in Japan. A total of more than 2 million lightning strokes are observed for the four years and the number of annual lightning strokes is closely related to the weather conditions in summer. Lightning occurs all over Japan in summer but occurrence of lightning is concentrated in the coastal area of the Sea of Japan in winter. Data of thunderdays are compared with the data observed by the Japan Meteorological Agency. The relationship between number of lightning strokes and thunderdays is also obtained. It changes season by season and it is very difficult to express the relations with a single formula.