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In recent decades, the eastern Pacific green turtle (recognized as the subspecies Chelonia mydas agassizii, i.e., the black turtle) has occasionally been recorded around the Japanese Archipelago. However, whether its occurrence is a recent ecological response to global climate change or a response to oceanic conditions remains unknown. In the present study, we conducted a literature search using historical Japanese natural history documents called "Honzou Gaku," and present the first record of trans‐Pacific migration of the black turtle during the Edo period (1600–1868). This finding adds substantial knowledge to our understanding of the life history of this sea turtle species. Thus, a literature search on the historical heritage of other animal and plant species could provide more information about their past or lost biodiversity. [ABSTRACT FROM AUTHOR]

The origin of electrical activity accompanying volcanic ash plumes is an area of heightened interest in volcanology. However, it is unclear how intense an eruption needs to be to produce lightning flashes as opposed to "vent discharges," which represent the smallest scale of electrical activity. This study targets 97 carefully monitored plumes <3 km high from Sakurajima volcano in Japan, from June 1 to 7, 2015. We use multiparametric measurements from sensors including a nine-station lightning mapping array and an infrared camera to characterize plume ascent. Findings demonstrate that the impulsive, high velocity plumes (>55 m/s) were most likely to create vent discharges, whereas lightning flashes occurred in plumes with high volume flux. We identified conditions where volcanic lightning occurred without detectable vent discharges, highlighting their independent source mechanisms. Our results imply that plume dynamics govern the charging for volcanic lightning, while the characteristics of the source explosion control vent discharges. Plain Language Summary There are different types of electrical activity that occur within volcanic ash plumes. One well-known type is volcanic lightning, which creates the familiar flashes of visible light. Another, lesser-known type is called "vent discharges," which are tiny and invisible but create a peculiar signal known as continual radio frequency. Vent discharges are important because they sometimes occur very early in an eruption and may provide a way to give early warning of volcanic hazards. For this study, we used a specialized instrument called a lightning mapping array to measure the electrical activity during small eruptions at Sakurajima volcano. We explored when lightning flashes and vent discharges occurred during 97 different explosions. First, we found that the two types did not always happen in the same explosion, showing they are caused by different processes. Second, we found that vent discharges were more likely to occur when the explosive plume rose quickly, possibly because rock breakup and particles rubbing together create a static charge close to the vent. In contrast, lightning flashes occurred when the plume had high volume flux. These findings give clues about how to link electrical signals to eruptive processes for volcano monitoring. [ABSTRACT FROM AUTHOR]

We have recovered instrumental temperature and pressure observations from Tokyo covering the periods 1825-1828, 1839-1855, and 1872-1875; from Yokohama covering the periods 1860-1871 and 1874; from Osaka covering the periods 1828-1833 and 1869-1871; and from Kobe covering the periods 1869-1871 and 1875-1888. The newly recovered records contain data before the 1870s, which is a period where, until recently, no instrumental data in Japan were believed to exist. Their addition to the previous backward extension of Japanese series, as based on the recently recovered intermittent Dejima/Nagasaki series 1819-1878, implies that the nineteenth-century extension of the Japanese instrumental record no longer contains major temporal gaps. The recovered data were used for a preliminary calculation of the west-Japan temperature (WJT) series, which is a representative temperature series for the area. The existence of a warm epoch in the 1850s over W-Japan and a downward temperature trend till the early twentieth century, as previously inferred from documentary data, is confirmed from the WJT data. The pressure data implies that the temperature differences between the nineteenth and twentieth centuries are at least partly caused by a change in atmospheric circulation. Copyright © 2006 Royal Meteorological Society. [ABSTRACT FROM AUTHOR]