The phenomenon of swing bowling, in which a cricket ball veers sideways during flight, is not influenced by humidity, researchers say.
Cricketers and sport scientists alike have long hypothesised that high humidity may increase the swing effect.
But precise 3-D studies of cricket balls under varying humidity showed no effect on the balls' shapes.
A report due in Procedia Engineering instead suggests that cloud cover increases swing by stilling the air.
Much like the path of a "curve ball" in baseball or a looping corner kick in football, the swing effect comes from setting up different kinds of air flow on opposite sides of the ball - smooth or "laminar" flow on one side and chaotic "turbulent" flow on the other.
But why the effect is more noticeable during some matches, and even some days in the same match, has had researchers and players stumped.
"Lots of scientists have always tried to discuss this idea around cricket ball swing and the effect of atmospheric conditions, and people talk about humid days being really important," said study co-author David James of Sheffield Hallam University's Centre for Sport Engineering Research.
"The leading hypothesis as to why cricket balls swing was around the fact that the seam on the cricket ball will swell on a humid day, becoming more pronounced, and that might lead to more swing," he told BBC News.
Dr James and his colleagues John Hart at Sheffield and Danielle MacDonald at AUT University in New Zealand made use of the centre's "climate chamber", in which atmopheric conditions can be tightly controlled.
They used a 3-D laser scanner to monitor differently conditioned balls reacted under varying humidity, but found humidity had no detectable effect on the ball's geometry.
Instead, they have pitched in another idea: that bright sunshine - or the lack of it - is to blame for variation in swing.
"When the ground heats, it makes convection currents which make the air rise off the cricket pitch - that creates turbulence in the air on a sunny day," Dr James explained.
"On a cloudy day you get stiller air, because you don't get these convection currents coming off the ground."
Stiller air does less to affect the imbalance of smooth and chaotic flow on either side of the ball that leads to swing, so cloud cover could indirectly be the culprit.
Dr James concedes that the team's hypothesis must now be put to a test under controlled conditions, but they are convinced that humidity is not the variable that should put batters on the back foot.
"We fairly rigorously went through every possible thing around humidity and debunked it," he said.
The most important scientific discovery of the decade!
The most important scientific discovery of the decade!
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”
Re: The most important scientific discovery of the decade!
I see....The most important scientific discovery of the decade!
Not much of a decade then....
Re: The most important scientific discovery of the decade!
Must be a decade for "important scientific discovery" comparable to 730-740.....
Re: The most important scientific discovery of the decade!
One day, one day, I will take you to a first class test match, and instruct you in the delights of the world's finest sport.
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”
Re: The most important scientific discovery of the decade!
Oh googly...
Sometimes it seems as though one has to cross the line just to figger out where it is
Re: The most important scientific discovery of the decade!
Love your sig Keld.
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”
Re: The most important scientific discovery of the decade!
In other news:Lord Jim wrote:Must be a decade for "important scientific discovery"....
"Water Is Wet"
Your collective inability to acknowledge this obvious truth makes you all look like fools.
yrs,
rubato
Re: The most important scientific discovery of the decade!
Gob wrote:One day, one day, I will take you to a first class test match, and instruct you in the delights of the world's finest sport.
Also beer.
Re: The most important scientific discovery of the decade!
Ah yes, a warm sunny day at say, Lords or Edgebaston or Headingley, with England vs Aus, and a pint of Scruttocks Old Dirigible for breakfast.
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”