Bubble Formation and Modification in the Sea and its Meteorological Significance

Abstract

It is believed that the vast majority of the airborne salt nuclei arise from bursting bubbles at the air—sea water interface. Four natural mechanisms for the production of these bubbles have been studied. These are whitecaps, rain, snow and supersaturation of the surface waters of the sea due to spring warming. The bubble spectra from whitecaps and snowflakes have been measured and semi-quantitative and qualitative observations have been made on the bubble spectrum produced by raindrops. No evidence of bubble production by spring warming has been obtained.
 All of the measurements show that a majority of the bubbles are < 200 microns diameter and, in the case of bubbles from snowflakes, < 50 microns. In the vicinity of a breaking wave the bubble production rate is about 30 cm−2 sec−1.
 Due to the effects of surface tension in increasing the bubble internal pressure all bubbles < 300 microns will go into solution even at sea water air saturations of 102 percent. Bubbles < 20 microns will go into solution at saturations up to 115 percent! The solution time for small bubbles of about 10 microns is about 10 sec and is not markedly affected by the water saturation percentage.
 It is concluded that the effects of the rate of solution of bubbles in sea water can, under some conditions, play a significant role in modifying the initial bubble spectrum. This, in turn, should influence the spectrum of airborne nuclei.

An acoustic estimate of methane concentration in a water column in regions of methane bubble release

“…This method, as well as acoustic methods based on the Doppler effect [25], makes it possible to determine flows from a mov ing ship; for kilometric depths, the sensitivity of the method is higher: up to 1 cm/s. The conventional methods of measuring the meth ane flux, which are based on placing special gas traps [26] or on optical observations of rising bubbles [27], estimate the flux from the total volume of bubbles passing through a horizontal plane per unit time (upward methane flux). However, to determine the desired dissolved methane profile in water, it is neces sary to know the methane flux into water, which is related to bubble dissolution, rather than the upward methane flux related to vertical methane transfer by rising bubbles.…”

The Cloud Nucleating Properties and Mixing State of Marine Aerosols Sampled along the Southern California Coast

“…Sea spray aerosol, composed of sea salt and marine organic material, is a natural aerosol source emitted to the atmosphere when bubbles produced from breaking waves burst at the air-sea interface ejecting particulate matter into the atmosphere during the process [16][17][18]. Primarily composed of sodium chloride, sea salt has been shown to be the most hygroscopic aerosol with κ = 1.28-1.4 for fresh sea salt [8,19].…”

Mechanism for the Water-to-Air Transfer and Concentration of Bacteria

“…Breaking waves are probably the most prolific source of bubbles, but rain and snow impacting on the surface are also effective bubble producers (13).…”