NAEA News, Volume 62, Number 5, October–November 2020

Fast coronal mass ejections (CMEs), X‐class flares, solar energetic particle (SEP) events, and interplanetary shocks were abundantly observed during the episode of intense solar activity in late October and early November 2003. Most of the 80 CMEs originated from three active regions (NOAA ARs 484, 486, and 488). We compare the statistical properties of these CMEs with those of the general population of CMEs observed during cycle 23. We find that (1) the 2003 October–November CMEs were fast and wide on the average and hence were very energetic, (2) nearly 20 percent of the ultrafast CMEs (speed ≥2000 km s−1) of cycle 23 occurred during the October–November interval, including the fastest CME of the study period (∼2700 km s−1 on 4 November 2003 at 1954 UT), (3) the rate of full‐halo CMEs was nearly four times the average rate during cycle 23, (4) at least sixteen shocks were observed near the Sun, while eight of them were intercepted by spacecraft along the Sun‐Earth line, (5) the CMEs were highly geoeffective: the resulting geomagnetic storms were among the most intense of cycle 23, (6) the CMEs were associated with very large SEP events, including the largest event of cycle 23. These extreme properties were commensurate with the size and energy of the associated active regions. This study suggests that the speed of CMEs may not be much higher than ∼3000 km s−1, consistent with the free energy available in active regions. An important practical implication of such a speed limit is that the Sun‐Earth travel times of CME‐driven shocks may not be less than ∼0.5 day. Two of the shocks arrived at Earth in <24 hours, the first events in ∼30 years and only the 14th and 15th documented cases of such events since 1859.

Abstract. In India, stubble burning is frequently practiced in the dominant rice-growing states of the Indo-Gangetic Plains, primarily in Punjab, Haryana and Uttar Pradesh. We attempted monitoring and mapping of the active fire events in real time for all the 3 states by acquiring thermal datasets from 3 different sensors i.e. Visible Infrared Imaging Radiometer Suite (VIIRS) at 375 m aboard Sumo-NPP, Moderate-Resolution Imaging Spectro-Radiometer (MODIS) at 1000 m aboard Terra & Aqua, and Advanced Very High Resolution Radiometer (AVHRR) at 1,100 m aboard NOAA 18/19 & MetOp 1/2, made available by IARI Satellite Ground Station during Kharif crop harvest season (October–November) 2018. The standard algorithm of detection of the temperature of a pixel at (4.0 µm and/or 10 to 12 µm) and its difference from the temperature of surrounding pixels was employed for day and night passes. Analysis of active fire locations detected from VIIRS, MODIS and AVHRR between 01st October and 30th November 2018 suggests continuing practice of stubble burning with a total of 75563 burning events distributed as 59695, 9232 and 6636 in Punjab, Haryana and Uttar Pradesh, respectively. District-wise monitoring showed a significant upsurge of fire events during the study period in the south-western and eastern districts of Punjab. Intense fire was witnessed in northern districts of Haryana and western districts of Uttar Pradesh. Comparative analysis shows that the burning events in the current year up till 30th November 2018 are 85% of the events detected in 2017 and about 59.10% of the events detected in 2016. It implies that the burning of rice stubble in the current year has reduced significantly over the past years due to various scheme implemented by the State and Central government.

Alkenones and particulate fluxes in sediment traps from the central equatorial Pacific

Fewer follicles and of variable size are found at any time on the mare ovary compared with other livestock species, also influenced by seasonal variation. This is reflected on the population of cumulus–oocyte complexes (COC) collected that is characterised by a high heterogeneity. Recovered immature oocytes presumably need different culture conditions. The main factors contributing to this high heterogeneity are the follicle diameter, the status of the cumulus oophorus, and the reproductive seasonality. Therefore, the aim of the present study was to assess the nuclear chromatin configuration and the oocytes–cumulus cell gap junction-mediated communication (GJC) functionality in COC of different origins because these parameters are indicative of the oocyte’s metabolic state and should be taken into account when designing IVM strategies. The COC with compact (Cp) or expanded (Ex) cumulus oophorus were collected from follicles of different diameters (<1, 1–2, and >2 cm) in October–November, January–February, and April–May. The GCJ functionality was assessed by Lucifer Yellow microinjection and chromatin configuration was evaluated by Hoechst and Lacmoid staining, after cumulus cells removal. Data were obtained from a total of 1003 oocytes and were analysed by chi-squared test. Overall, GJC functionality was impaired in the majority of Ex COC in each follicle category, even though a certain proportion of them had open GJC (% of Ex COC with open GJC was 39.7, 29.3, and 39.3 in <1, 1–2, and >2 cm follicles, respectively). Moreover, the proportion of Ex COC with open GJC did not differ significantly between periods (% of Ex COCs with open GJC in October–November, January–February, and April–May was, respectively, 43.3, 28.6, and 41.7 in <1 cm follicles; 45.5, 19.3, and 26.47 in 1–2 cm follicles; 66.7, 50, and 16.7 in >2 follicles). On the contrary, the majority of Cp COC from follicles <1 and 1–2 cm, showed open GCJ in October–November and April–May, whereas they decreased significantly in January–February. This tendency was not maintained in Cp COC from follicles >2 cm, where GJC functionality did not differ significantly between periods (% of Cp COC with open GJC in October–November, January–February, and April–May was, respectively, 74.4, 35.7, and 75 in <1 cm follicles; 73.8, 42.1, and 67.7 in 1–2 cm follicles; 58.3, 58.3, and 68.6 in >2-cm follicles). Chromatin configuration analysis revealed that the highest proportion (23.9%) of oocytes with fibrillar chromatin was found in Cp oocytes from <1 cm follicles, whereas the proportion of oocytes with fibrillar chromatin ranged from 5.4 to 12.5% in the other groups. Moreover, the increase in follicle diameter was generally associated with an increase of chromatin condensation in Cp COC. Interestingly, the chromatin configuration distribution did not differ significantly among seasons. Our data could be useful in setting up new in vitro cultural strategies aimed to improve horse-assisted reproductive technology efficiency as well as in the understanding of horse oocyte biology. Funding: Grant no. 26096200 ‘Ex Ovo Omnia’ from Regione Sardegna & Lombardia and ‘Dote Ricerca Applicata’ (VL and IT).

Farmer field trials on determination of critical timings of rodenticide bait application in sugarcane crop were conducted in two districts of Punjab (India) during 2007–2010 for modification in already recommended practice. Sugarcane crop at all the experimental locations was surrounded by rice–wheat crops in rotation and infested predominantly with Bandicota bengalensis. Results of experiments conducted during 2007 and 2008 at two locations each revealed no significant difference in overall reduction in rodent activity and damage between fields given single (during October–November) and double (first in July and second in October–November) rodenticide treatments due to rapid rebuild up in rodent population after every treatment thus indicating the need of two treatments as per the previous recommendation. Results of experiment conducted during 2009–2010 at two locations revealed significantly (P < 0.05) higher reduction in rodent activity and damage in fields given third treatment during December–January with 0.005% bromadiolone @ 2 kg/ha than in fields given third treatment with 2% zinc phosphide @ 2 kg/ha and fields given only first two treatments. This may be due to significantly (P < 0.05) low acceptance of zinc phosphide bait compared to bromadiolone bait by rodents in these months. Present studies suggest that for protecting sugarcane fields from rodent damage at different crop stages, three rodenticide treatments, first in July, second in October–November with two rodenticide baitings @ 1 kg/ha each at the interval of 15 days and third treatment in December–January with single baiting of 0.005% bromadiolone @ 2 kg/ha may be applied.

Effect of the COVID-19 pandemic on adolescent mental health and substance use up to March, 2022, in Iceland: a repeated, cross-sectional, population-based study

North-western Indian Ocean (NIO), especially Arabian Sea (AS), experiences intense seasonally reversing winds and undergoes a seasonal change in the turbulence energetics. Given the importance of Arabian Sea dynamics on the Indian monsoon, a numerical investigation was carried out to study the energy budget using MOM 5. Model domain is between 32 to 118&amp;#8304; E and 28&amp;#8304; S to 30&amp;#8304; N and is forced with daily varying 10 year averaged atmospheric fluxes. Lateral open boundaries are prescribed with sea surface height anomaly (SSHA) in combination with radiation condition. Vertical profiles of temperature and salinity are also prescribed at lateral boundaries. Using the averaged forcing, model is run for 10 years as spin up and brought into equilibrium and then forced with 5 years inter-annually varying dataset, which is used for analysis. Though the model domain covers quite an extensive part of Indian Ocean, but our analysis is limited in the NIO between 8&amp;#8304;S to 30&amp;#8304;N and 32 to 82&amp;#8304;E (hereafter called as Analysis domain). Model produced data is seasonally averaged into 4 seasons, DJF (December to February), MAM (March to May), JJAS (June to September), and ON (October-November). Currents are well represented by model and are validated with OSCAR currents. Ocean properties such as Sea Surface Temperature, Sea Surface Salinity and Mixed Layer Depth produced by model are within reasonable bias. The investigation of TKE indicates that it has seasonal and spatial preference. Depth averaged over 30m TKE, indicates that it is strongest in JJAS and DJF along the Somalia coast and equatorial region of NIO respectively. In MAM, TKE is strong in south-western AS, close to equator and in ON, a reminiscence of TKE is seen along the Western AS (WAS). Spatial average vertical profile of TKE for 3 regions, [1: 8&amp;#8304;S to 30&amp;#8304;N and 32 to 82&amp;#8304;E (Analysis domain), 2: 4&amp;#8304;S to 4&amp;#8304;N and 56 to 82&amp;#8304;E (Western Equatorial Indian Ocean, WEIO), and 3: 4 to 12&amp;#8304;N and 45 to 55&amp;#8304;E (WAS)] is shown. Analysis reveals that TKE is highest in upper 200m and decreases with depth, and in DJF, it is maximum in WEIO and least in WAS, but quite interestingly, after 150m till about 250m, TKE increases in WAS. This could indicate strong subsurface turbulent activity in WAS in DJF. In JJAS, TKE is almost 4 times that of DJF and is highest in WAS and least in WEIO. In WAS, turbulence produced due to buoyancy is suppressed by production flux being negative which indicates inverse energy cascade in DJF. In JJAS, production flux is strongly positive in WAS with negative production in the Great Whirl eddy and in the equatorial region. Turbulence is produced by buoyancy as well near horn of Africa, yet dissipation is weak in the said region, which could be due to strong positive transport. Production shows weak positive features in WAS and is strongly negative in equatorial region in MAM and ON. Buoyancy flux is negative in WAS in MAM and ON, indicative of stable stratification.

The Okavango River Basin (ORB) which includes a renowned World Heritage site Okavango Delta, contains highly biodiverse ecosystems. Most of its rural population relies on rain-fed subsistence farming. Limited research has been done on future changes in rainfall and temperature in this region. Here, such changes are analysed for the periods 2030–2059 (near term) and 2070–2099 (long term), relative to the historical period 1985–2014. The analysis is based on the Coupled Model Intercomparison Project Phase 6 (CMIP6), under the shared socioeconomic pathways (SSPs) SSP245 and SSP585. The projected changes vary over the ORB. For rainfall, the models project some significant decreasing trends over Ngamiland in the central/southern ORB, but none are significant over the northern ORB. The significant trends during the near term period include those projected by the model average (-30.60 mm/decade) in March–April (MA) under the SSP585 scenario. Some significant decreasing rainfall trends have also been found in December-February (DJF), but none are significant in October–November (ON). DJF is the main growing season whereas ON (MA) is the onset (end) of the rainy season. For temperature, significant warming trends have been found over both Ngamiland and the northern ORB, with the strongest warming in ON particularly during the near term period. For this ON season over the northern ORB, under the SSP585 (SSP245) scenario, the model average projects a warming trend of 0.56 °C/decade (0.67 °C/decade). These findings may help with the management of agricultural activities, water resources and the highly biodiverse ecosystems in the ORB.

The role of biomass burning agricultural emissions in the Indo-Gangetic Plains on the air quality in New Delhi, India

Ground-based ambient air monitoring was conducted at five different locations in and around Patiala city (29°49′–30°47′N Latitude, 75°58′–76°54′E Longitude) in Northern India in order to determine the impact of open burning of rice (Oriza sativa) crop residues on concentration levels of suspended particulate matter (SPM), sulphur dioxide (SO2) and nitrogen dioxide (NO2). Covering sensitive, residential, agricultural, commercial and urban areas, sampling of these pollutants was organised during August 2006 to January 2007 and August 2007 to January 2008 casing two rice crop residue burning periods (October–November) using a high volume sampling technique combined with gaseous sampling systems. Gravimetric analysis was used in the estimation of total suspended particulate matter (TSPM) whereas SO2 and NO2 concentration was determined using spectrophotometer (Specord205, Analytikjena). Monthly average concentrations of SPM, SO2 and NO2 have shown significant up and down features at all the selected sampling sites during the study period. Monthly average concentrations (24 hour) of SPM, SO2 and NO2 varied from 100 ± 11 µg m−3 to 547 ± 152 µg m−3, 5 ± 4 µg m−3 to 55 ± 34 µg m−3 and 9 ± 5 µg m−3 to 91 ± 39 µg m−3. Substantially higher concentrations were recorded at the commercial area site as compared to the other sampling sites for all the targeted air pollutants. Levels of SPM, SO2 and NO2 showed clear increase during the burning months (October–November) incorporated with the effect of meteorological parameters especially wind direction, precipitation and atmospheric temperature.

[1] October–November Caribbean hurricane activity can have profound impacts on the region through loss of life and devastation of property. Large-scale climate parameters associated with active late seasons in the Caribbean are investigated in this paper. Among the primary features that are noted are atmospheric and oceanic conditions typical of La Nina and a larger-than-normal Atlantic Warm Pool as well as reduced trade wind strength in the western tropical Atlantic. A two-predictor statistical model has been developed to forecast the number of hurricane days in the Caribbean during October–November. The first predictor is the July–September–averaged Nino 3.4 index, a measure of El Nino-Southern Oscillation, while the second predictor measures July–September–averaged sea surface temperatures in the western part of the tropical Atlantic extending into the Caribbean, which very closely correlates with the size of the Atlantic Warm Pool. These two predictors can hindcast approximately 58% of the variance in the number of October–November Caribbean hurricane days over the period from 1982 to 2010 when a drop-one cross validation procedure is applied. The predictors also correlate significantly with physical features in the Caribbean basin that are known to impact tropical cyclones. While these strong correlations between predictors and physical features extend back to an independent period from 1900 to 1981, the correlations between individual predictors and October–November hurricane days degrade considerably during the earlier period.

Italian ryegrass is a major weed problem in wheat (Triticum aestivum L.) production worldwide. Two separate studies were conducted in Stoneville, Mississippi to evaluate: (1) the efficacy of herbicides available to Mississippi producers for controlling glyphosate-resistant (GR) Italian ryegrass (control study), and (2) fall burndown herbicide seed suppression study. Results of the control study showed that flufenacet/metribuzin EPOST followed by (fb) pinoxaden LPOST (standard treatment) provided 93% control of GR Italian ryegrass. Some other treatments provided comparable Italian ryegrass control (92% to 97%) as the standard treatment in 2017. Italian ryegrass control in the seed suppression study was 100%, 100%, 67.5%, 97%, and 99.5% from the application of the following treatments: (1) S-metolachlor + flumioxazin + paraquat in October–November fb glyphosate + clethodim in January–February fb gramoxone as needed (weed-free check); (2) S-metolachlor + flumioxazin + paraquat in October–November; (3) field cultivator (disk) in October–November; (4) glyphosate + clethodim in January–February; and (5) field cultivator in October–November fb glyphosate + clethodim in January–February, respectively. The remaining Italian ryegrass from the application of treatments 3, 4, and 5 produced 65,700; 1008; and 9 seeds m−2, respectively. Seed suppression study highlights the importance of 100% control that is required to manage GR Italian grass.

Distribution of inorganic nitrogen-containing species in atmospheric particles from an island in the Yellow Sea

Temporal changes of phytoplankton biomass in the western Black Sea shelf waters: Evaluation by satellite data (1998–2018)

The feeding ecology of juvenile (&lt; 140 mm TL) and adult (&gt; 140 mm TL) capelin (Mallotus villosus) in the St. Lawrence River Estuary and western Gulf of St. Lawrence was studied between October 1974 and October 1975. Both juveniles and adults fed almost exclusively on zooplankton. Three prey totally dominated the diet. Copepods were numerically most abundant but euphausiids were dominant in terms of biomass. Appendicularians ranked third in both number and biomass. This differed from the diet of capelin in the Canadian Atlantic only to the extent that amphipods replace appendicularians in the diet in the Atlantic and large copepods are more abundant in the diet there. A shift in diet occurred during growth. Premetamorphic capelin (&lt; 75 mm TL) consumed small prey exclusively: invertebrate eggs, cyclopoid copepods, and diatoms predominated. The diets of juvenile (75–139 mm TL) and adult (&gt; 140 mm TL) capelin overlapped considerably but a pronounced shift from small copepods to adult euphausiids occurred at ~ 140 mm TL. Early morning and evening feeding peaks occurred between May and August. A single midday feeding peak prevailed in October–November. Feeding of adult capelin was active in the spring prior to spawning but virtually ceased during spawning. Juvenile capelin fed actively throughout spring and summer. The daily ration of zooplankton by capelin was estimated to be 5% of wet body weight in summer May–September and ~ 2.5% in October–November. Year-to-year variations in average daily consumption in excess of 100 000 t have occurred between 1972 and 1978 and average daily consumption has declined by up to 310 000 t during the same interval. This significant year-to-year and long-term release of zooplankton from predation by capelin may be an important regulator of changes in year-class strength in other species of the area, notably arctic cod, Boreogadus saida and short-finned squid, Illex illecebrosus.Key words: capelin, Mallotus villosus; Gulf of St. Lawrence, ecology, food habits, daily ration, estuaries, zooplankton, multispecies interactions, arctic cod, Boreogadus saida; squid, Illex illecebrosus