Sea-surface temperature bucket, Crawford type

Sea-surface temperature bucket, formerly the property of the Meteorological Office Marine Branch, of a type invented by British engineer Allan Crawford in the 1960s.

Buckets like this were used by mariners to collect samples of seawater in order to make observations of sea surface temperature from the 1960s. While simpler buckets had been used for over a century, it was difficult to ensure the accuracy and consistency of the data. The temperature of the bucket itself influenced readings, and sometimes the temperature of the sample or thermometer varied before the reading was made. This design was patented by the engineer Allan Crawford, who sought to address some of the key issues. The bucket’s rope tail orientated it in the water so it collected a sample of water correctly and at the right depth, and a flap enabled the thermometer to be read without removing it from the bucket.