scholarly journals Comparison of Vaisala radiosondes RS41 and RS92 launched over the oceans from the Arctic to the tropics

2017 ◽  
Vol 10 (7) ◽  
pp. 2485-2498 ◽  
Author(s):  
Yoshimi Kawai ◽  
Masaki Katsumata ◽  
Kazuhiro Oshima ◽  
Masatake E. Hori ◽  
Jun Inoue
Keyword(s):  
Relative Humidity ◽  
Bering Sea ◽  
Western North Pacific ◽  
North Pacific Ocean ◽  
Tropical Indian Ocean ◽  
The Arctic ◽  
Pressure Measurements ◽  
Correction Table ◽  
The Tropics ◽  
Better Than

Abstract. To assess the differences between the RS92 radiosonde and its improved counterpart, the Vaisala RS41-SGP radiosonde version with a pressure sensor, 36 twin-radiosonde launches were made over the Arctic Ocean, Bering Sea, western North Pacific Ocean, and the tropical Indian Ocean during two cruises of R/V Mirai in 2015. The biases, standard deviations, and root mean squares (rms's) of the differences between the RS41 and RS92 data over all flights and altitudes were smaller than the nominal combined uncertainties of the RS41, except that the rms of the differences of pressure above 100 exceeded 0.6 hPa. A comparison between daytime and nighttime flights in the tropics revealed that the pressure difference was systematically larger during the day than at night above an altitude of 4.5 km, suggesting that there was some effect of solar heating on the pressure measurements, but the exact reason is unclear. The agreement between the RS41 and RS92 temperature measurements was better than the combined uncertainties. However, there were some noteworthy discrepancies presumably caused by the wet-bulbing effect on the RS92 radiosonde and the stagnation of the balloon. Although the median of the relative humidity differences was only a little more than 2 % of the relative humidity at all altitudes, the relative humidity of the RS92 was much lower than that of the RS41 at altitudes of about 17 km in the tropics. This dry bias might have been caused by the incomplete solar radiation correction of the RS92, and a correction table for the daytime RS92 humidity was calculated. This study showed that the RS41 measurements were consistent with the specifications of the manufacturer in most cases over both the tropical and polar oceans. However, further studies on the causes of the discrepancies are needed.

scholarly journals Comparison of Vaisala radiosondes RS41 and RS92 in the oceans ranging from the Arctic to tropics

2017 ◽  
Author(s):  
Yoshimi Kawai ◽  
Masaki Katsumata ◽  
Kazuhiro Oshima ◽  
Masatake E. Hori ◽  
Jun Inoue
Keyword(s):  
Relative Humidity ◽  
Bering Sea ◽  
Tropical Indian Ocean ◽  
The Arctic ◽  
Northwestern Pacific ◽  
Pressure Measurements ◽  
Northwestern Pacific Ocean ◽  
Correction Table ◽  
The Tropics ◽  
Better Than

Abstract. To assess the differences between the RS92 radiosonde and its improved counterpart, the Vaisala RS41-SGP radiosonde that has a pressure sensor, 36 twin-radiosonde launches were made over the Arctic Ocean, Bering Sea, northwestern Pacific Ocean, and the tropical Indian Ocean during two cruises of the R/V Mirai in 2015. The biases, standard deviations, and root mean squares (RMSs) of the differences between the RS41 and RS92 data over all flights and altitudes were smaller than the nominal combined uncertainties of the RS41, except that the RMS of the differences of pressure above 100 hPa exceeded 0.6 hPa. A comparison between daytime and nighttime flights in the tropics revealed that the pressure difference was systematically larger during the day than at night above an altitude of 4.5 km, the suggestion being that there was some effect of solar heating on the pressure measurements, but the exact reason is unclear. The agreement between the RS41 and RS92 temperature measurements was better than the combined uncertainties. However, there were some noteworthy discrepancies that were presumably caused by the “wet-bulbing” effect and stagnation of the balloon. Although the median of the relative humidity differences was only a little more than 2 % of the relative humidity at all altitudes, the relative humidity of the RS92 was much lower than that of the RS41 at altitudes of about 17 km in the tropics. This dry bias might have been caused by the incomplete solar radiation correction of the RS92, and a correction table for the daytime RS92 humidity was calculated. This study showed that the RS41 measurements were consistent with the specifications of the manufacturer in most cases over both the tropical and polar oceans. However, further studies of the causes of the discrepancies are needed.

scholarly journals How Does the Arctic Sea Ice Affect the Interannual Variability of Tropical Cyclone Activity Over the Western North Pacific?

2021 ◽  
Vol 9 ◽  
Author(s):  
Hao Fu ◽  
Ruifen Zhan ◽  
Zhiwei Wu ◽  
Yuqing Wang ◽  
Jiuwei Zhao
Keyword(s):  
Sea Ice ◽  
Bering Sea ◽  
North Pacific ◽  
Western North Pacific ◽  
Japan Sea ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Arctic Sea ◽  
The Japan Sea ◽  
The Bering Sea

Although many studies have revealed that Arctic sea ice may impose a great impact on the global climate system, including the tropical cyclone (TC) genesis frequency over the western North Pacific (WNP), it is unknown whether the Arctic sea ice could have any significant effects on other aspects of TCs; and if so, what are the involved physical mechanisms. This study investigates the impact of spring (April-May) sea ice concentration (SIC) in the Bering Sea on interannual variability of TC activity in terms of the accumulated cyclone energy (ACE) over the WNP in the TC season (June-September) during 1981–2018. A statistical analysis indicates that the spring SIC in the Bering Sea is negatively correlated with the TC season ACE over the WNP. Further analyses demonstrate that the reduction of the spring SIC can lead to the westward shift and intensification of the Aleutian low, which strengthens the southward cold-air intrusion, increases low clouds, and reduces surface shortwave radiation flux, leading to cold sea surface temperature (SST) anomaly in the Japan Sea and its adjacent regions. This local cloud-radiation-SST feedback induces the persistent increasing cooling in SST (and also the atmosphere above) in the Japan Sea through the TC season. This leads to a strengthening and southward shift of the subtropical westerly jet (SWJ) over the East Asia, followed by an anomalous upper-level anticyclone, low-level cyclonic circulation anomalies, increased convective available potential energy, and reduced vertical wind shear over the tropical WNP. These all are favorable for the increased ACE over the WNP. The opposite is true for the excessive spring SIC. The finding not only has an important implication for seasonal TC forecasts but also suggests a strengthened future TC activity potentially resulting from the rapid decline of Arctic sea ice.

Two new species of Suberitida (Porifera, Heteroscleromorpha) from the Bering Sea

Zootaxa ◽  
2017 ◽  
Vol 4338 (3) ◽  
pp. 546
Author(s):  
HELMUT LEHNERT
Keyword(s):  
New Species ◽  
Bering Sea ◽  
North Atlantic Ocean ◽  
North Pacific Ocean ◽  
First Record ◽  
The Arctic ◽  
Valid Species ◽  
The North ◽  
Two New Species ◽  
The Bering Sea

Two new species, Plicatellopsis borealis and Spongosorites beringensis, from the Bering Sea are described; both belong to genera previously not reported from the area. The genus Plicatellopsis, Burton, 1932 (Porifera, Suberitida, Suberitidae) contains five valid species, all recorded from the southern hemisphere. The record of P. borealis n. sp. from the Bering Sea is consequently the first record of the genus from the northern hemisphere. The genus Spongosorites Topsent, 1896 (Porifera, Suberitida, Halichondriidae) contains 22 valid species but none reported from the North Pacific Ocean, Bering Sea or the Arctic Ocean. The geographically closest records are six species occurring in the North Atlantic Ocean. So the description of Spongosorites beringensis n.sp. is the first record of the genus in the region. 

Interannual to Interdecadal Variability in the Japan Sea Based on a New Gridded Upper Water Temperature Dataset

2004 ◽  
Vol 34 (11) ◽  
pp. 2382-2397 ◽  
Author(s):  
Shoshiro Minobe ◽  
Akinori Sako ◽  
Makoto Nakamura
Keyword(s):  
Water Temperature ◽  
North Pacific ◽  
Western North Pacific ◽  
North Pacific Ocean ◽  
World Ocean ◽  
Japan Sea ◽  
The Arctic ◽  
Optimal Interpolation ◽  
The Japan Sea ◽  
Central North Pacific

Abstract A new gridded water temperature dataset of upper 400-m depths (0, 50, 100, 200, 300, and 400 m) for the Japan Sea (or East Sea) is produced by using an optimal interpolation technique from 1930 to 1996, based on oceanographic observations collected in the World Ocean Database 1998. The temperature data are analyzed by a complex empirical orthogonal function (CEOF) with six levels combined using the data for a period from 1957 to 1996, during which most of gridded data are available. Before calculating the CEOFs, low-pass or high-pass filters (cutoff period at 7 yr) are applied to separate interannual and decadal temperature changes, respectively. One interannual and two decadal CEOF modes are identified. The interannual first CEOF mode is characterized by the energetic variability around and south of the subpolar front in the western Japan Sea, accompanied by northward and northeastward phase propagations emanating from the Tsushima Strait. The decadal first CEOF mode exhibits a broad structure prevailing over the whole Japan Sea, but large amplitudes are trapped by the subpolar front, with 60°–90° phase lags between the northeastern and southwestern Japan Sea. The decadal second CEOF mode has a localized structure with strong correlations in the Yamato Basin. The relation between the atmosphere and ocean is analyzed by a correlation analysis of wintertime sea level pressures (SLPs) onto the temporal coefficients of the CEOF modes. The interannual first CEOF mode is accompanied by the SLP anomalies over the western North Pacific Ocean with steep SLP gradients over the Japan Sea, suggesting that this mode is forced by local wind anomalies associated with the SLP changes over the western North Pacific. The decadal first CEOF mode is likely to be caused by changes of the east Asian winter monsoon due to the SLP variability of the northern part of the Siberian high, which is closely associated with the decadal fluctuations of the Arctic Oscillation and the North Atlantic Oscillation. The second decadal CEOF mode is accompanied by high SLP correlations over the central North Pacific associated with strength changes of Aleutian lows, suggestive of remote forcing from the central North Pacific.

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