Concentrations of elements, including S, Al, Si, K, Ca, Ti, and Fe, in aerosols sampled sequentially with 3.7‐hour time resolution over a 2‐week period in April and May 1979 at the Mauna Loa Observatory, Hawaii, indicate that long‐range transported ‘background’ crustal dust aerosol can reach concentrations in excess of 20 μg m−3 with more than 8μg m−3 of additional sulfate. Favorable regional meteorology after known dust storm episodes, as well as similarities in crustal element ratios, point to dry areas of northern China as the major source region for this crustal aerosol. Time series analyses for crustal elements show a dominant 21‐hour but no 24‐hour period, a result that can be accounted for by a diurnally varying source process with subsequent modification of periodicity, e.g., by wind speed convergence during transport. Time‐dependent associations between S and the crustal elements, especially high coherency at long periodicities, also imply a long‐range transport for much of the S, possibly from populated areas in eastern Asia, including China and Japan. This source may contribute much of the sulfuric acid believed to cause the relatively high acidity of rainwater observed at higher altitudes in Hawaii. Mauna Loa Observatory, at 3400 m altitude, is apparently an excellent location for detecting Asian dust and pollutant transport during spring with little interference from Hawaii‐derived aerosol.

The first experimental evidence of detecting the neutrons correlated with the natural atmospheric lightning discharges (NALD) was obtained with Lead‐Free Gulmarg Neutron Monitor (LFGNM) operating at High Altitude Research Laboratory, Gulmarg, Kashmir, India, and was reported in the year 1985. The neutron observations still continue with LFGNM. However, the current configuration of LFGNM is the upgraded version of the system used earlier to record neutron bursts (in the recording period of 320 μs in four successive electronic gates of 80 μs each) supposedly originating from an NALD. In the current system the neutron recording time period/interval has been extended to 1260 μs with 63 successive gates of 20 μs each. The system also simultaneously records the differential times—maximum up to 14—between the consecutive strokes of a multistroke lightning flash. The distance between an NALD channel and LFGNM setup is determined empirically by making use of the time delay (td)/time of flight (TOF) measurement of the first detected neutron subsequent to the sensing of the electrostatic field variation caused by the initiation of an NALD in the ambient atmosphere of the LFGNM setup. Assuming a priori incident energy as 2.45 MeV of the detected neutrons supposedly generated due to the fusion of deuterium ions in the lightning discharge channel leads to quantifying the neutron emission flux if the NALD channel distance with respect to the LFGNM setup is established. In this paper we discuss the experiment and the time profiles of several of a large number of the major neutron burst events recorded with LFGNM in association with NALDs. Moreover, a rare and an extraordinary neutron burst event, in terms of its associated “td/TOF” of first detected neutron after triggering, recorded by this system is specifically discussed. In this event, the recorded TOF of 14 μs of the escaping neutron detected by the system immediately after getting triggered by the NALD that struck a nearby tree found located just around 300 m (physically measured) away from the detector position indicates the energy of the detected neutron ϵn ≈2.45 MeV. In the light of this only event, we, therefore, cautiously suggest deuteron‐deuteron fusion reaction, 2H(2H,n)3He, as one of the possible mechanisms of the neutron generation correlated with an NALD. Nonetheless, the observations so far have reconfirmed production of neutrons in an NALD.

The seasonal cycle of the phytoplankton biomass in the North Atlantic Ocean (20°S to 70°N) is discussed using monthly mean surface pigment concentration fields from the Nimbus 7 coastal zone color scanner (CZCS) for the period of December 1978 through December 1979. The temporal and spatial distributions of surface pigments are compared with quantities derived from the First GARP Global Experiment (FGGE) wind data set (1000‐mbar streamlines, Ekman upwelling, horizontal Ekman transport and |τ|3/2), Climate Analysis Center (CAC) sea surface temperature (SST) fields, concurrent hydrographic station data, and climatological mixed‐layer depths and heat fluxes. The objective of the analysis is to clarify the role of some physical mechanisms that regulate the supply of nutrients to the euphotic zone at different locations in the basin and at different times of the year. It is observed that during this period, the spring bloom was, in most locations, sustained for 2 to 3 months. At a given latitude the onset of the spring bloom varied by several months and, in some cases, could be referred to as a fall bloom. In other cases there were both spring and fall blooms. Time series at 11 selected sites throughout the basin are used to illustrate, in detail, the relation of phytoplankton biomass to local physical forcing. Finally, separate analyses of the mean pigment concentrations for the shelf and open ocean regions indicate that the phytoplankton of both regimes had spring and fall blooms of equal magnitude, the spring bloom being located at northern latitudes and the fall bloom in the equatorial region. Analysis of the open ocean Ekman upwelling field shows similar peaks approximately 2 months in advance of the surface pigment concentration peaks.

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