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Selected photographs taken during the unmanned Apollo 6 mission have been subjected to stereoscopic photogrammetry to determine the heights of cloudbases and the tops of convective clouds. Examples of how these calculated heights may be used to infer the physical characteristics of the ambient atmosphere are shown. The detail within the photographs permits contouring of cloudtop heights within mesoscale systems. Accuracies of height determination are estimated to be ±250 m.

A procedure for synthesizing 500-mb. height and temperature data over oceanic areas using only sea level data as an input is developed. The procedure is tested by comparing the synthetic data to observed 500-mb. data at 4YN and 4YP and by comparing 500-mb. synthetic data charts to 500-mb. charts based on observed data. The North Pacific is chosen for the latter test. The 500-mb. height variations given by synthetic data compare favorably with the observed height variations at 4YN and 4YP. While certain errors are apparent in the synthetic 500-mb. chart it does show many of the features of the chart produced from observed data.

Use of detailed analyses of an Apollo 6 stereographic photograph of a smoke plume which originated in southern Arizona and crossed over into Mexico to illustrate how high-resolution photography can aid meteorologists in evaluating specific air pollution events. Photogrammetric analysis of the visible smoke plume revealed that the plume was 8.06 miles long and attained a maximum width of 4000 ft, 3.0 miles from the 570-ft chimney emitting the effluent. Stereometric analysis showed that the visible top of the plume rose nearly 2400 ft above stack top, attaining 90% of this total rise 1.75 miles downwind from the source. Photometric analysis of the plume revealed a field of plume optical density that portrayed leptokurtic and bimodal distributions rather than a true Gaussian distribution. A horizontal eddy diffusivity of about 650,000 sq cm/sec and a vertical eddy diffusivity of 230,000 sq cm/sec were determined from the plume dimensions. Neutron activation analysis of plume samples revealed the elemental composition of the smoke to be copper, arsenic, selenium, indium and antimony, with trace amounts of vanadium and scandium.