The latitudinal dependence in the trend of snow event to precipitation event ratio

Precipitation phase is expected to shift from solid to liquid with temperature rising, which would in turn bring challenges to regional water resource management. Although in recent decades, consistent decreasing trends in the ratio of snowfall to precipitation rate in a warming climate have been found across multiple regions, a global view of the trends in the precipitation partitioning has not been established. In this study, we investigated the global trends of annual rain and snow frequency of occurrences and the ratio of number of snow events to number of precipitation events (SE/PE ratio) using land station and shipboard synoptic present weather reports from 1978 to 2019. Results show that when averaged over all qualified land stations and over the shipboard reports, both the annual rain frequency and snow frequency decrease over the 42 years. Over both land and ocean, the averaged SE/PE ratio has a significant decreasing trend. Moreover, the trend of SE/PE ratio shows a strong latitudinal dependence. At the mid- and low latitudes in the Northern Hemisphere, the SE/PE ratio has a decreasing trend. In contrast, at high latitudes, the SE/PE ratio has an increasing trend.

Makrofauna Tanah Di Lahan Hortikultura Desa Losari Kecamatan Sumowono Kabupaten Semarang

Abstrak: Makrofauna tanah merupakan bagian dari biodiversitas tanah yang memiliki peran penting dalam perbaikan sifat fisik, kimiawi, dan biologi tanah melalui proses imobilisasi dan humifikasi. Desa Losari merupakan salah satu desa di Kecamatan sumowono Kabupaten semarang yang terletak di kaki Gunung Ungaran sehingga keadaannya masih asri dan alami. Penelitian ini dilakukan pada Bulan Juli 2020. Tujuan penelitian ini adalah untuk mengetahui bagaimana tingkat keanekaragaman jenis makrofauna tanah yang ada di kawasan lahan pertanian Desa Losari dengan tanaman yang berbeda. Pengambilan data dilakukan dengan dua metode yaitu Pit fall trap dan Hand sorting. Hasil penelitian menunjukkan bahwa tingkat keanekaragaman jenis di lokasi penelitian tergolong rendah. Total makrofauna tanah yang tercatat di lokasi penelitian sebanyak 37 jenis yang terdiri dari 3 filum. Lahan pertanian tanaman kubis (stasiun I) memiliki tingkat keanekaragaman yang tertinggi dibandingkan dengan stasiun lainnya dengan nilai H' = 1,064. Filum dengan jumlah terbanyak di lokasi penelitian adalah filum Arthropoda sebanyak 33 jenis dari 98 total jenis makrofauna tanah yang telah ditemukan.Kata Kunci: keanekaragaman makrofauna tanah; hortikultura; pit fall trap; hand sorting.Abstract: Soil macrofauna is part of soil biodiversity which has an important role in improving the physical, chemical, and biological properties of soil through immobilization and humification processes. Losari Village is one of the villages in Sumowono District, Semarang Regency, which is located at the foot of Mount Ungaran so that the condition is still beautiful and natural. This research was conducted in July 2020. The purpose of this study was to determine the level of diversity of soil macrofauna species in the agricultural area of Losari Village with different plants. Data were collected by two methods, namely Pit fall trap and Hand sorting. The results showed that the level of species diversity in the study location was low. The total soil macrofauna recorded at the research location were 37 species consisting of 3 phyla. Cabbage farming land (station I) has the highest level of diversity compared to other stations with a value of H' = 1.064. The phylum with the highest number in the research location was Arthropoda phylum with 33 of the 98 total soil macrofauna species that had been found.Keywords: soil macrofauna diversity; horticulture; pit fall trap; hand sorting.

Group IV humpback whales: their status from aerial and landbased surveys off Western Australia, 2005

Single platform aerial line transect and land-based surveys of Southern Hemisphere Group IV humpback whales were undertaken to provide absoluteabundance estimates of animals migrating northward along the western Australian coast during June–August 2005. The aerial survey was designedto cover the whole period of northward migration but the resulting estimates from that survey alone could only, at best, provide relative abundanceestimates as it was not possible to estimate g(0), the detection probability along the trackline, from the data. Owing to logistical constraints, theland-based survey was only possible for a much shorter period (two weeks during the expected peak of the migration in mid-July). This paperproposes three methods that utilise these complementary data in different ways to attempt to obtain absolute abundance estimates. The aerial linetransect data were used to estimate relative whale density (for each day), allowing absolute abundance from the land-based survey to be estimatedfor the short period of its duration. In turn, the land-based survey allowed estimation of g(0) for the aerial survey. Absolute estimates of abundancefor the aerial survey were obtained by combining the g(0) estimate with the relative density estimates, summing over the appropriate number ofdays. The most reliable estimate of northward migrating whales passing the land station for the period of the land-based survey only was 4,700(95% CI 2,700–14,000). The most reliable estimate for the number of whales passing through the aerial survey region for the duration of that survey(55 days from June through to August) was 10,300 (95% CI 6,700–24,500). This is a conservative estimate because the duration of the aerial surveywas almost certainly shorter than the period of the migration. Extrapolation beyond the end of this survey was considered unreliable, but abundancefrom the estimated start of the migration to the end of the survey (87 days from mid-April to August) was estimated to be 12,800 (95% CI 7,500–44,600). The estimated number of whales depends crucially on the assumed migration and period of migration. Results for different migrationparameters are also presented. The point estimates of abundance, whilst higher than those from a previous survey in 1999 (when adjusted for surveyduration) are not significantly so. The peak of the whales’ distribution was found at c.90m water depth.

ENDURUNS: An Integrated and Flexible Approach for Seabed Survey Through Autonomous Mobile Vehicles

The oceans cover more than two-thirds of the planet, representing the vastest part of natural resources. Nevertheless, only a fraction of the ocean depths has been explored. Within this context, this article presents the H2020 ENDURUNS project that describes a novel scientific and technological approach for prolonged underwater autonomous operations of seabed survey activities, either in the deep ocean or in coastal areas. The proposed approach combines a hybrid Autonomous Underwater Vehicle capable of moving using either thrusters or as a sea glider, combined with an Unmanned Surface Vehicle equipped with satellite communication facilities for interaction with a land station. Both vehicles are equipped with energy packs that combine hydrogen fuel cells and Li-ion batteries to provide extended duration of the survey operations. The Unmanned Surface Vehicle employs photovoltaic panels to increase the autonomy of the vehicle. Since these missions generate a large amount of data, both vehicles are equipped with onboard Central Processing units capable of executing data analysis and compression algorithms for the semantic classification and transmission of the acquired data.

ARCTIC

The review of the Arctic basin seismicity for 2013 is presented. It is based mainly on the data from the sta-tions of world network, located outside the basin. The data from a single local seismic station was used. It was "Franz Josef Land" station with two sets of seismic sensors, ZF1 and ZF2. The station is a part the Ar-khangelsk network, operating in the region since September 2011. There were 38 earthquakes with mb=3.0–4.6 in the Arctic basin in total. A map of their epicenters is provided. 28 of them are connected with the seismically active zone, which extends through the deep-water part of the Arctic basin to the shelf of the Laptev Sea. For two earthquakes, the parameters of focal mechanisms are given according to the GCMT da-ta. The magnitude frequency distribution for 2013 is compared with the distributions for 1990-2012. The level of seismic energy released in 2013 is 1.3 times lower than in 2012 and 1.6 times higher than its average one for 23 previous years. The distribution of earthquakes in the Arctic region in 2013 is presented.

Comparative study on wave hindcasting using wind downscaling data at Bojong Salawe Beach

The wind data have a crucial role in shore construction engineering, but the availability data is commonly rare. Some research and recording station provide wind data with four times data record in a day. This research calculated the wave as resulted of the downscaled wind data from four times a day to twenty four times a day recording. The research done by comparing several data obtained from satellite record and land-station record. The results show similarity in wind velocity and dominance direction but have significant differences of wave height and the direction of wave from difference record locations.