How thunderstorms are generated in clouds continues to be not absolutely understood. However John Latham, who has died aged 83, did a lot to elucidate the bodily processes of cloud electrification, cloud lightning and precipitation – how water falls from clouds in varied kinds. Later he proposed a method through which clouds might present an important if non permanent position in decreasing the influence of world warming.

The analysis he started beneath John (BJ) Mason in 1958 at what’s now Imperial School London targeted on the position of ice crystals in cloud electrification. His laboratory research of thunderstorms concerned the idea of a temperature distinction between graupel – tender hail – and ice crystal surfaces. He and Mason developed the Temperature Gradient Principle and offered numerical predictions of the mechanism. Like all theories of thunderstorm electrification, it proved controversial.

After acquiring a lectureship in 1961 at Umist, now a part of Manchester College, John constructed a succession of chilly rooms so as to examine thunderstorm electrification.

He and colleagues devised the “who grows quicker” speculation, exploring whether or not beneath sure circumstances throughout ice-particle collisions the particle rising quicker from the vapour turns into positively charged and the opposite negatively charged, resulting in the event of electrical fields that can lead to lightning discharges. This conclusion, subsequently supported by additional information, stays the idea for fashions of electrification to this present day.

Lightning strikes over Kolkata. Though concerned with analysing natural phenomena down to a molecular level, John Latham never lost a sense of wonder at the imaginative effect they have on us.
Lightning strikes over Kolkata. Although involved with analysing pure phenomena right down to a molecular degree, John Latham by no means misplaced a way of surprise on the imaginative impact they’ve on us. {Photograph}: Piyal Adhikary/EPA

Maybe his biggest contribution got here in 1979, in relation to droplet progress and microphysics in heat clouds – these containing water vapour and the droplets condensed from it, reasonably than ice. A significant downside in cloud physics was to elucidate how rain in heat clouds fashioned in an noticed time of about 20 minutes. Not one of the fashions on the time had been in a position to clarify this.

John steered a novel speculation for the method, which he termed “inhomogeneous mixing”. On this account, discrete blobs of dry air are carried alongside into the clouds, utterly evaporating close by droplets, whereas others additional away are unaffected. Lowering the general focus of drops decreases the competitors for the accessible water vapour and permits the most important drops to develop quicker and rain to develop throughout the noticed time.

In 1988, John left Umist for the National Center for Atmospheric Research in Boulder, Colorado.

Two years after arriving there, he addressed the issue of world warming by proposing that marine cloud brightening (MCB) might be briefly used to mirror incoming photo voltaic radiation again. It might obtain this by means of exploiting what is named the Twomey effect: for a similar quantity of liquid water, numerous small droplets mirror extra incoming photo voltaic radiation than a smaller variety of bigger ones. He proposed to result in this radiative cooling by utilizing a sea-salt spray of specified dimension, generated from wind-driven ships, and from 2008 onwards printed the supporting science.

Researchers on the Centre for Climate Repair, Cambridge, and elsewhere are presently engaged on prototypes to check the thought. US companies have helped sponsor the work, and parallel research are being carried out on the College of Washington, Seattle.

As a author, John printed six collections of poetry, together with All-Clear (1990), Sailor Boy (2006) and From Professor Murasaki’s Notebooks on the Effects of Lightning on the Human Body (2017). The title poem of the final had gained second prize in 2006 within the Nationwide Poetry Competitors in Britain. He additionally produced brief fiction, performs for BBC Radio 4 and a surrealistic novel, Ditch-Crawl (2006).

Although involved with analysing pure phenomena right down to a molecular degree, John by no means misplaced a way of surprise on the imaginative impact they’ve on us, as within the poem Double-jointed (from the Murasaki assortment):

I’m again now within the Rockies,

a spurting, crackling fireplace

sends flame-shadows scudding

spherical stripped-log cabin partitions,

and a lightweight up excessive, outdoors, reveals

us snowflakes crazy-dancing into oblivion.

In his later years, whereas dwelling in that cabin in Gold Hill, close to Boulder, he wrote the poem Nightfall Phrases (from Crossing Over, 2017), as he turned conscious of the onset of dementia: “I’m not afraid of it, not a lot, not but, / however I can really feel it coming, the dawning darkish, / wisps of altostratus that subdue the solar”. In 2018 he returned to his birthplace, Frodsham, in Cheshire.

His father, Jack (William John), was an electrician and ran a store within the village together with his mom, Ruth (nee Barrow). From Helsby highschool John went to Imperial, the place he accomplished his PhD.

At Umist he was awarded a DSc (1968) earlier than being appointed professor, and I knew him as a colleague there from 1985. He gave workshops on the physics of lightning at universities world wide, his work was recognised by the Royal Meteorological Society, and he served as president of the Worldwide Fee on Atmospheric Electrical energy (1975-83). The thought that his work may assist fight international warming stored him working at NCAR so long as he might, and we continued to collaborate on analysis tasks.

In 1961 John married Ann Bromley, additionally from Frodsham, they usually had 4 kids; they divorced amicably in 1992. He was predeceased by two sons, Rob and Mike, and is survived by his kids David and Rebecca, seven grandchildren, Samuel, Shane, Jessica, Natasha, Molly, James and Evie, and a great-grandchild, Tamara.

John Latham, local weather physicist, born 21 July 1937; died 27 April 2021



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