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We carried out two campaign observations over the southwestern coastal land and adjacent sea of Sumatera Island, Indonesia, during November-December 2015 (pre-YMC 2015, hereafter Y15) (49 days) and November 2017-January 2018 (YMC-Sumatra 2017, hereafter Y17) (61 days). We deployed two land observation sites in Bengkulu city on the southwestern coast of Sumatra Island with various kinds of instruments including an X-band dual polarization (DP) and operational C-band Doppler radars, and the R/V Mirai over the coastal sea with a C-band DP radar. Intensive 3-hourly soundings were conducted both over the land and the vessel during both periods. Synoptic conditions during the Y15 (Y17) corresponded to El Niño (La Niña) and large scale cloud areas of active Madden-Julian Oscillation (MJO) passed over Sumatra Island in the about later (former) 10 days of the period, i.e., most of both campaign periods were convectively MJO inactive phases. Rainfall at Bengkulu during Y15 showed clear diurnal variation with active thunderstorms every day (31 days) during the Y15 until MJO active phase onset over Sumatra. Whereas rainfall diurnal variation in Y17 was quite unclear and its peak time was delayed approximately 2 hours than that in Y15 though both periods corresponded to mostly MJO inactive phases. In particular, the thunderstorm during Y17 was quite a few (9 days) and only a short time within an hour. Characteristics that brought different convective activities between two campaign periods, e.g., diurnally developed local winds, atmospheric instabilities, and spatiotemporal variations of radar echo distribution, were analyzed for further discussion., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Remotely derived environmental variables, including sea surface height anomaly SSHA, sea surface temperature SST, chlorophyll-a chl-a, eddy kinetic energy EKE, mixed layer data set of argo float MLD, Nino 3.4 index, and bigeye tuna catch data for the period 1997–2008, were used to analyse ocean climate variability and how they relate to the hotspots of bigeye tuna catch in the eastern Indian Ocean off Java. The empirical orthogonal function EOF was performed to obtain a more detailed structure of the spatio-temporal ocean variability in the region. The results showed that the first EOF modes of chl-a, SSHA, and SST accounted for 42.8%, 36.5%, and 27.4% of total variance, respectively, and these corresponded to the interannual signal. The maps of spatial patterns of the first EOF modes of SSHA, SST, and chl-a gave very typical values for cold-water SSHA, low SST, and high chl-a concentration along the southern coast of the Indonesian archipelago; and warm-water SSHA, high SST, and low chl-a concentration in the offshore region to make frontal areas along the latitudinal line around 10–12o S. The EOF analysis further revealed a strong relationship between the El Nino event and favourable oceanographic conditions, resulting in a significant increase in bigeye tuna catch. The average hook rate of 0.71 0.43 was recorded during El Nino La Nina. Major hotspots were located away from the confluence region and frontal areas around 11–16° S and 110–118° E and were thus demonstrated as the most favourable oceanographic conditions for bigeye tuna fishing in the eastern Indian Ocean off Java.

A-14-year (1979-1993) image satellites of Solar Radiation, NOAA and SeaSurface Height Anomaly of TOPEX/POSEIDON and ERS-2 have been used to study a reducing solar radiation received by the Earth (global dimming) and to predict local weather anomaly for the future climate prediction in the Indonesian region. The result shows that a dimming of solar radiation is of 16.6% during 14-year observation. It is higher than the mean increasing of global dimming of 2 - 3% for every decade. This explicitly indicates that the air pollution in the form of aerosols from industrial sectors has large contributions to this this dimming process. At the other side, there is a trend of dominant warm water in the southern Jawa-Bali that affect on the increasing of rainfall intensity in the Indonesian region. We predict that flood and a longer dark during the day time, and more variative local weather change will be more frequently happen in the Indonesian region in the futu

第25回大気圏シンポジウム（2011年2月21日-22日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県, 25th Atmospheric Science Symposium (February 21-22, 2011. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000072017, レポート番号: Ⅲ-5

第24回大気圏シンポジウム（2010年2月18日-19日. 宇宙航空研究開発機構宇宙科学研究本部（JAXA)(ISAS)）, 相模原市, 神奈川県, 24th Atmospheric Science Symposium (February 18-19, 2010. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000073013, レポート番号: Ⅲ-1

第23回大気圏シンポジウム（2009年2月26日-27日. 宇宙航空研究開発機構宇宙科学研究本部（JAXA)(ISAS)）, 相模原市, 神奈川県, 23rd Atmospheric Science Symposium (February 26-27, 2009. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 11名, 資料番号: SA6000074004, レポート番号: Ⅰ-4

第22回大気圏シンポジウム（2008年2月27日-28日. 宇宙航空研究開発機構宇宙科学研究本部（JAXA)(ISAS)）, 相模原市, 神奈川県, 22nd Atmospheric Science Symposium (February 27-28, 2008. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000075018, レポート番号: Ⅲ-5