The most important weather forecast in history
In memory of my father Hans who, in 1944, took part in the liberation of Europe with the Royal Engineers in the Italian Campaign. –Benny Peiser
1) The Weather Forecast That Saved D-Day
Christopher Klein
Years of detailed planning went into the D-Day invasion on June 6, 1944, but success hinged on one element that no military commander could control—the weather. In the days leading up to the invasion, Allied meteorologists delivered the most important weather forecast in history. If they got it wrong the Allies might have lost tens of thousands of men and World War II might have been lost forever.
In contrast to the bright morning about to dawn over Portsmouth, England, on June 4, 1944, gloom settled over the Allied commanders gathered inside Southwick House at 4:15 a.m. Years of preparation had been invested in the invasion of Normandy, but now, just hours before the launch of D-Day operations, came the voice of Group Captain James Stagg urging a last-minute delay. As Operation Overlord’s chief meteorological officer, the lanky Brit was hardly a battlefield commander, but the ultimate fate of D-Day now rested in his decision-making.
The disappointed commanders knew that the list of potential invasion dates were only a precious few because of the need for a full moon to illuminate obstacles and landing places for gliders and for a low tide at dawn to expose the elaborate underwater defenses installed by the Germans. June 5, chosen by Allied Supreme Commander Dwight Eisenhower to be D-Day, was the first date in a narrow three-day window with the necessary astronomical conditions. The massive Normandy landings, however, also required optimal weather conditions. High winds and rough seas could capsize landing craft and sabotage the amphibious assault; wet weather could bog down the army and thick cloud cover could obscure the necessary air support.
The critical, but unenviable task of predicting the English Channel’s notoriously fickle weather fell to a team of forecasters from the Royal Navy, British Meteorological Office and U.S. Strategic and Tactical Air Force, and as D-Day approached, storm clouds brewed inside the meteorological office. Observations from Newfoundland taken on May 29 reported changing conditions that might arrive by the proposed invasion date. Based on their knowledge of English Channel weather and observations, the British forecasters predicted the stormy weather would indeed arrive on June 5. The American meteorologists, relying on a differing forecasting method based on historic weather maps, instead believed that a wedge of high pressure would deflect the advancing storm front and provide clear, sunny skies over the English Channel.
Stagg, the only meteorologist allowed direct contact with Eisenhower, had to make the final call. Although the sky was clear and wind negligible in the early hours of June 4, Stagg believed foul weather was only hours away. He sided with his fellow British colleagues and recommended a postponement. Knowing that the weather held the potential to be an even fiercer foe than the Nazis, a reluctant Eisenhower agreed in the early hours of June 4 to delay D-Day by 24 hours.
On the other side of the English Channel, German forecasters also predicted the stormy conditions that indeed rolled in as Stagg and his fellow Brits had feared. The Luftwaffe’s chief meteorologist, however, went further in reporting that rough seas and gale-force winds were unlikely to weaken until mid-June. Armed with that forecast, Nazi commanders thought it impossible that an Allied invasion was imminent, and many left their coastal defenses to participate in nearby war games. German Field Marshal Erwin Rommel even returned home to personally present a pair of Parisian shoes to his wife as a birthday present.
German Luftwaffe meteorologists, however, relied on less sophisticated data and models than their Allied counterparts, says John Ross, author of “The Forecast for D-Day: And the Weatherman behind Ike’s Greatest Gamble.” “The Allies had a much more robust network of weather stations in Canada, Greenland and Iceland; of weather ships and weather flights over the North Atlantic and observations by secret agreement from weather stations in the neutral Republic of Ireland,” he says. Those weather stations, in particular one at a post office at Blacksod Point in the far west of Ireland, proved crucial in detecting the arrival of a lull in the storms that Stagg and his colleagues believed would allow for an invasion on June 6. As rain and high winds lashed Portsmouth on the night of June 4, Stagg informed Eisenhower of the forecast for a temporary break. With the next available date for an invasion nearly two weeks away, the Allies risked losing the element of surprise if they waited. In spite of the pelting rain and howling winds outside, Eisenhower placed his faith in his forecasters and gave the go-ahead for D-Day.
The weather during the initial hours of D-Day was still not ideal. Thick clouds resulted in Allied bombs and paratroopers landing miles off target. Rough seas caused landing craft to capsize and mortar shells to land off the mark. By noon, however, the weather had cleared and Stagg’s forecast had been validated. The Germans had been caught by surprise, and the tide of World War II began to turn.
Weeks later, Stagg sent Eisenhower a memo noting that had D-Day been pushed to later in June, the Allies would have encountered the worst weather in the English Channel in two decades. “I thank the Gods of War we went when we did,” Eisenhower scribbled on the report.
He could also have been thankful for Stagg overruling the advice of the American meteorologists who wanted to go on June 5 as planned, which Ross says would have been a disaster. “The weather over Normandy contained too much cloud cover for Ike’s greatest strategic asset, the Allied air forces, to effectively protect the landings from German armor, artillery and infantry reserves. Winds were too strong for the deployment of paratroopers to secure bridges and crossroads inland from the beaches thus preventing German reinforcement of coastal positions. Waves were too high for landing craft to put soldiers and supplies ashore. The key element of surprise—location and time—would have been lost, and the conquest of western Europe could well have taken another year.”
2) D-Day: The Sceptical Meteorologists Who Surprised The Nazis By Saying ‘Yes’ To June 6
Simon Pearson
The outcome of D-Day was decided not on the beaches of Normandy, but by weather systems in the mid-Atlantic and the ability of rival teams of meteorologists to interpret the forces of nature. The Americans were confident in long-range five-day forecasts. The British were sceptical, believing they could forecast only two days ahead at best. The teams clashed repeatedly.
The outcome of D-Day was decided not on the beaches of Normandy, but by weather systems in the mid-Atlantic and the ability of rival teams of meteorologists to interpret the forces of nature.
As unfavourable conditions developed during that early summer 70 years ago, three teams of meteorologists produced reports for the Allied commander, General Dwight D Eisenhower, who laid down the conditions necessary for invasion — and his preferred date: June 5. Across the Channel, a single team of Germans watched the weather.
One of the men who took part in this great drama was Lawrence Hogben, a New Zealand naval officer, who, as a Rhodes Scholar, studied mathematics at New College, Oxford and trained as a meteorologist with the Royal Navy. Today, he lives in a care home in southern France, the country he helped to liberate and, even at the age of 98, retains vivid memories of events in June 1944.
Hogben had already distinguished himself as a naval officer before he was asked to work with Geoffrey Wolfe, a Cambridge-educated engineer, in the Admiralty team forecasting the D-Day weather.
As an instructor lieutenant, responsible for training, intelligence and meteorology on HMS Sheffield, he had witnessed several major naval actions: the sinking of the German battleship Bismark in May 1941; the Battle of the Barents Sea — when Sheffield engaged the German pocket battleships Admiral Hipper and Lutzow in the Arctic in December 1942; and Operation Torch, the invasion of French North Africa a year later.
Decorated for bravery and promoted instructor lieutenant-commander, he had also developed his skills as a weatherman. “OnSheffield, I was making forecasts every day from the data coming in and from the state of the sea,” he says.
Hogben and Wolfe were one of two British teams. The second, put forward by the Met Office, consisted of Charles Douglas, the chief forecaster who was known for his photographic memory of meteorological events, and Sverre Pettersen, a Norwegian. The third team was American, with Irving Krick and Benny Holzman, two well-known weathermen from the California Institute of Technology. Each day, the three teams reported their findings to Group Captain James Stagg, a Scot who had been superintendent of the Kew Gardens observatory in 1939. He briefed Eisenhower.
For operational reasons, the American commander needed a full moon, a low tide, little cloud cover and light winds so that troops in landing craft could get ashore quickly, the gliders and parachutists could operate efficiently, and the Allied fighters and bombers could find their targets.
The forecast was not good. Indeed, climatic data suggested the odds against the forecasters finding the right conditions was 13-1 in June 1944. The Americans were confident in long-range five-day forecasts. The British were sceptical, believing they could forecast only two days ahead at best. The teams clashed repeatedly.
According to William Bryant Logan, author of Air: The Restless Shaper, they succeeded, “not because of the brilliant work of any solitary forecaster, but because a group of forecasters imitated the weather. They jostled, yelled, scribbled, and cast malevolent looks at one another. They fought it out and voted. And in the end, they were just right enough.”
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“evanmjones says:
June 6, 2014 at 10:20 pm
I just think that by 1945 the Russian army was too big and too good for us to beat. I think they would have hit us for six if we’d tried.”
Size of the force was not the determining factor. Supplies and an army not prepared for ~40 below ZERO CENTIGRADE temperatures. Diesel froze in tanks and injectors. The Germans did not understand that, to “save” a vehicle, you needed to run the engine 24×7. The Germans, with Hitler commited beyond capacity, could not supply suitable material on the Eastern front, the African front etc. And failed as we know.
Stalin killed more people than in both world wars. Even more than ‘Flu after WW1. Lets not talk about Mao, 50mil (est).
I am not sure D-day was such a success. Landing was forced, to be sure, with overwhelming superiority and light losses, but allied troops were bottled up in Normandy for 2 critical months. That’s when Central Europe went to hell for 5 decades.
It was only General Patton who had proper fighting spirit, but he was kept out of battle for too long.
” The Germans had been caught by surprise, and the tide of World War II began to turn.”
The tide in the European theatre had turned in 1942, when the Germans were defeated at El Alamein and (more importantly) Stalingrad.
evanmjones says:
June 6, 2014 at 7:28 pm
Von Braun was “helpful”.
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It was more than von Braun, though he gets the credit. Our Goddard, the “Father of Modern Rocketry,” was playing with toys while the Germans were weaponizing rockets. The difference was in the Germans’ team approach. Their rocketeers had worked together as hobbyists, then as professionals, learning together and working out problems together. Our Goddard was a loner, and wouldn’t even listen to his assistant’s suggestions. Bankrolled by Lindbergh, our government stayed out of it, as they thought rocket development was in good hands, and it wasn’t costing them anything – critical during the First Great Depression. The U.S. was absolutely shocked by the V-2. In a different set of circumstances, such as Germany developing an atomic bomb, Goddard could have lost us the war. Yet we name our Space Flight Center for him. I would rather it be named for Capt. Robert Truax.
I think the most important weather forecast in history was the one that the Nazi Meteorological Office issued in 1942 which said. ‘Go for it Adolf, we’ve had a succession of very mild winters recently, you’ll be in Moscow by Christmas’!
Great story, thanks!
evanmjones says:
June 6, 2014 at 7:49 pm
You are welcome. Hope Europe makes better use of its freedom in future than so far. Same goes for us since fall of the USSR. Having been in Afghanistan in 2005, I’m not as optimistic as I was in the 1980s about the odds for freedom.
My son teaches Russians English in his spare time.
I never spoke a word. They didn’t want their advanced students nattering away in Russian as the teach showed off his Russian. They wanted to force them to communicate in English. They wanted someone who knew English backward and forward (and it didn’t hurt that I knew the hot WWII Eastern cities, I think).
They were good times. I brought in Monopoly sets and we had “Capitalism Day”. (Fines for speaking in anything but English strictly enforced.) They also play-acted “Twelve Angry Men” (original TV-script version) — and they all voted “guilty” . . .
Hope Europe makes better use of its freedom in future than so far.
Yet they’ve done worse.
Same goes for us since fall of the USSR. Having been in Afghanistan in 2005, I’m not as optimistic as I was in the 1980s about the odds for freedom.
There will be ups and downs. It’s a work in progress.
Our first thoughts should be of thanks to the men you served in that fight for freedom and especially to those who lost their life or were maimed, physically or mentally.
A few thoughts on the ‘what-if’ questions.
As a reader of history, but by no means an expert, my understanding is that D-Day was a very close run things and that quite late on the day Eisenhower prepared two statements for the press, one for success (which was issued) and one for failure.
So I am far from sure that a month’s delay would have beneficial. If the Germans had got any sort of idea of where the invasion was actually to take place and moved extra troops there, then it could have been a failure.
If the invasion had failed then maybe the invasion of southern France would have gone ahead but whether it would have been as successful (with troops available to be transferred there) is unlikely.
And the ability of the Allies to mount another invasion of northern France must also be questionable. Churchill’s work in getting the US to agree to the the invasions of North Africa, Sicily & Italy are, I believe, to be generally accepted as being largely because he knew how weak Britain was and that it could only commit a large army to the invasion of France once. On D-Day, the British Army was at its peak size but reducing quite rapidly thereafter, there were nowhere near enough new men available to replace those that were lost.
Britain supplied roughly half of the troops for D-Day. If Britain lost (dead, wounded & captured) another 60,000+ men in a failed D-Day (as it did in the Battle of France) plus a huge amount of equipment, it is questionable how much she would have been able to contribute to a second invasion. Would the US have staged another invasion if Britain could only supply, say, 10% of the troops?
On the matter of effectiveness of the, primarily, US/UK forces compares to the Soviet forces. In Six Armies in Normandy John Keegan looks at the numbers and concludes that the US/UK forces were more effective, as in 1,000s of Germans defeated per 10,000 of Allied troops deployed.
IIRC some of that is because of the quality of weapons available (some Soviet ones were excellent but a lot were poor) and the some because of the physical abilities of the troops. Central planning in the Soviet Union had created numerous shortages in the 20s & 30s and so lots of the troops had poor physique from childhood malnutrition. Hence the Soviets had to have a huge numerical advantage in order to defeat the Germans.
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Amen to that.
Whatever might have been going on behind the scenes, those guys weren’t concerned with the “what-ifs”. They were concerned with the “what-nows”.
What are we going to do with our “what now”?
James Bolivar DiGriz says:
June 7, 2014 at 10:52 am
Thanks for sharing your intriguing ideas, James. It has been said that Churchill intended to fight to the last American (!).
“Hence the Soviets had to have a huge numerical advantage in order to defeat the Germans.”
Which they did. The Battle of the Kursk Salient in summer, 1943, found the Soviets toying with the Germans. They knew of Operation Citadel, and had prepared intricate defenses, yet the Germans still killed Soviets 5 to 1. The Soviets had them to lose; the Germans didn’t.
The Soviets had 3 armies standing by while the Germans slugged it out against the entrenched defenders. It was not until the Great Tank Battle at Prokhorovka had swung the tide of battle that the Soviets cut lose the 3 armies.
Germany was too small a country to get involved in a war of attrition with the Soviets.
Some of the comments are a little silly. Of course if D-Day would have failed he would still have won the war. He had – or were soon to have – the A bomb. Most of our Jewish nuclear physicists at Los Alamos wanted to drop it on Germany not Japan. If the invasion had floundered, the war would have continued long enough for them to get their wish.
We were sending daylight bombers to Berlin by this time. The raids of 1944 were much less opposed than those of 1943. Germany was losing the war of attrition. They couldn’t stop an A Bomb on Berlin or any other place we might choose.
The principal point of the bombings was in fact D-Day. The explicit goal of Operation Point Blank was to clear the skies of German planes by D-Day. And that goal was met. There were almost no Nazi aircraft overhead on D-Day.
But D-0day was very, very important. The Germans had run the Brits out of France. The Brits had tried a sort of practice invasion at Dieppe and again been run off the continent. Our side needed a victory badly.
evanmjones says:
June 6, 2014 at 7:28 pm
When I was young, I often heard that we won the space race because our Germans were better than the Soviets’ Germans.
Von Braun was “helpful”.
I’m sure Werner thought Robert Goddard a big help.
The German’s started with Goddard’s liquid fueled rocket patents.
“””””…..Patrick L. Boyle says:
June 7, 2014 at 12:40 pm
Some of the comments are a little silly. Of course if D-Day would have failed he would still have won the war. He had – or were soon to have – the A bomb. Most of our Jewish nuclear physicists at Los Alamos wanted to drop it on Germany not Japan. If the invasion had floundered, the war would have continued long enough for them to get their wish. …..”””””
Not sure just who YOUR “our side”, was.
Do YOU have any authenticated statement by any named one of “Most of our Jewish nuclear physicists”, to support your assertion.? What makes you think they were all nuclear physicists.? You don’t really need a nuclear physicist to build an A-bomb. Some very good technologists; but the nuclear physics part of the puzzle was well understood, ahead of time.
As I recall, it was Japan, that attacked the USA; not Germany.
And after the desert test, there were precisely two atom bombs. Had Japan known there was NO third bomb; they simply would not have surrendered either.
I know exactly where I was when “””…The Germans had run the Brits out of France. The Brits had tried a sort of practice invasion at Dieppe and again been run off the continent. …””””
I also remember what “your side” was doing, at the time of Dunkirk, and also of their early successes in North Africa.
The “trial run” for D-Day I believe resulted in more than twice the total casualties that actually occurred on Utah beach on D-Day.
That tragic trial run, also resulted in changes of plans for the real thing.
Nobody knows, how many lives were saved on D-Day, as a result of what was learned on that trial run.
As they say, the best of Military plans work well; right up to the moment, that you first make contact with the enemy.
In the end, the whole world (both sides) won.
James Bolivar DiGriz says:
June 7, 2014 at 10:52 am
German defensive specialist Heinrici figured that he could handle ten to one odds, but 11 to one became problematical.
george e. smith says:
June 7, 2014 at 2:33 pm
The Manhattan Project A-bomb program was begun specifically with the German threat in mind. In October 1939, Alexander Sachs delivered to FDR a letter on the German nuclear program written by Leo Szilard (& others) & signed by Albert Einstein. Here’s the refugee physicists’ letter to FDR that got the ball rolling:
http://www.pbs.org/wgbh/americanexperience/features/primary-resources/truman-ein39/
“””””…..evanmjones says:
June 6, 2014 at 7:18 pm
I don’t believe the idea was to actually fight the soviets at that point as much as Patton was complaining about stopping at the Elbe and not advancing farther even though the Russians had not yet reached Berlin. Eisenhower ordered a halt at the Elbe River on April 12, nearly a month before the Russians got to Berlin…….”””””
If I’m not mistaken, Eisenhower simply stuck to the plan that was established by the politicians at Yalta. It was Roosevelt who went along with Stalin. Churchill had to bite his tongue; America was paying the bills.
Churchill’s subsequent “Iron Curtain” speech made it clear he knew Yalta was a big misteak.
And Eastern Europe could have been freed as early as 1956, when Soviet tanks waited outside Budapest for ten days, to see what the West would do. The west did nothing, and the Hungarian uprising was crushed.
Obama is just repeating what he read in the history books.
“””””…..milodonharlani says:
June 7, 2014 at 2:46 pm
george e. smith says:
June 7, 2014 at 2:33 pm
The Manhattan Project A-bomb program was begun specifically with the German threat in mind……”””””
Well I read the Einstein letter of August 1939. Doesn’t really describe any German A-bomb program; just Uranium.
Neither Great Britain, nor the USA, was engaged in a war at the time with Germany; and Pearl Harbor had not yet been attacked.
Military plans change with combat experience.
In light of Goddard’s experiments, wouldn’t rockets (which existed for a thousand years already), have seemed more plausible than A-bombs. Chadwick only discovered the neutron in 1932.
So why didn’t US do massive research on rockets ?
george e. smith says:
June 7, 2014 at 3:04 pm
Patton continued into Czechoslovakia after Ike decided not to go for Berlin. Yalta didn’t decide who would take Berlin.
As president, Ike felt NATO lacked sufficient power in theater to come to the aid of the Hungarians.
george e. smith says:
June 7, 2014 at 3:24 pm
Britain & France were at war with Germany in Oct 1939.
It took only six years after Chadwick discovered the neutron for Frisch, Hahn, Strassmann & Meitner to achieve fission. In fact, they only started work on the problem in 1935.
Szilard had the idea for a nuclear chain reaction while waiting for a street light in Bloomsbury in 1933.
Based upon the evidence cited in the letter, Sachs specifically warned FDR that the Germans were working on an A-bomb, which in fact they were. That’s why he ordered the army, navy & other departments to investigate the issue, which led to the Manhattan Project, relying heavily on European immigrants. Unfortunately, at least one of them was a Soviet spy, but then so were some of the Americans.
The west was deeply divided over the Suez Crisis at that time, with no chance of action whatsoever in Europe, even if the Soviet army had no right to stay in Hungary any longer after the Austrian State Treaty, not to mention waging war on the country. See an American perspective on that.
However, the real message was already delivered in 1945, when the US failed to take Prague which could have been done with no fight at all and the western allies miserably abandoned a true ally, Poland, the original casus belli altogether to one of the aggressors.
Patrick L. Boyle says:
June 7, 2014 at 12:40 pm
You are correct. By June, 1944, the Luftwaffe was out of the war. Except for the massive Krupp/Goering AAA effort. My father was a B-24 pilot, deployed to England in early 1945. He said he never saw a German plane in the air. But he saw lots of flak. He feared it terribly.
The Germans did not run out of planes; they ran out of pilots.
The postponement of the invasion was one of two 11th hour decisions that Ike had to make. The other, less well known, had to do with the deployment of the Airborne troops behind Utah and Omaha beaches.
As time for the invasion drew close Ike’s chief Air Commander, Air Chief Marshal Sir Trafford Leigh-Mallory, became ever more pessimistic about the chances for success of the planned airborne operations in the American sectors. He had protested the plan for the use of the airborne troops back in April and with the invasion looming his doubts and fears for their fate became even more pronounced. So on May 30th, he approached Ike and let his fears be known once again. He feared that the two fine American Airborne division were to be sacrificed in a “fatal slaughter” He believed the combination of unsuitable landing grounds and the anticipated resistance would be just too much for the troops to overcome. He was thinking that casualties could run over 70%. Ike wrote later that “… Mallory was, of course earnestly sincere. He was noted for his personal courage and was merely giving me, as was his duty, his frank convictions”.
Everyone in high command knew the airborne operations, and in particular those in the American sector were very hazardous operations. The aircraft, some with gliders in tow, would have to avoid the invasion fleet in order to prevent a possible repeat of what had happened in Sicily.
Their routes would take them by the channel islands where they would first be exposed to antiaircraft fire. Then they would have to fly across the Cherbourg Peninsula at less that 1,000 feet in full moon light over country where the German anti aircraft fire was normally heavy and put the troops where German units were known to be concentrated.
The transport aircraft, C-47s and C-46s, were not armored in any way and didn’t even have self sealing fuel tanks. The British made Horsa gliders that many American units were to use were made primarily of wood and aluminum tube and the US made WACO CG-4 gliders were made of plywood, aluminum tube and canvas. Neither offered any protection. (The only glider armored for D-day was the CG-4 that carried Brig. General Pratt, Artillery commander of the 101st Abn. Div. That armored plate on the bottom of his gilder probably cost him his life as it greatly altered the flight characteristics of the glider and probably resulted in the subsequent crash in which he was killed instantly and all others in the craft killed or seriously wounded. Pratt was the highest ranking allied Casualty on D-day.)
Ike was worried. His expert on the subject was telling him not to do it. He talked to Lt. Gen. Omar Bradly about it. Bradly told Ike “It’s [the airborne operations] risky, of course, but not half as risky as landing on Utah Beach without it….”. And that was really the bottom line. Ike thought about it overnight but it always came back to that.
He later wrote “It would be difficult to conceive of a more soul-racking problem….. If I deliberately disregarded the advice of my technical expert on the subject, and his predictions should prove accurate, then I would carry to my grave the unbearable burden of a conscience justly accusing me of the stupid, blind sacrifice of thousands of the flower of our youth.” But in the end he agreed with Bradly that without the Airborne troops the landings on the American beaches would most likely fail. So he had to say the airborne operations go on because risking 17,000 American airborne troops lives was the only way he felt the invasion had a chance of succeeding. The next morning he picked up the telephone and rang up Chief Air Marshal Mallory, and thanking him for his concern told him the invasion would proceed as planned.
“george e. smith says:
June 7, 2014 at 2:33 pm
The “trial run” for D-Day I believe resulted in more than twice the total casualties that actually occurred on Utah beach on D-Day.”
That would have been Slapton Sands, Devon, UK, where the entire town was evacuated 6 months or so before the exercise. There is an official death count of about 1000 US army troops (This figure apparently excludes Royal/US naval personnel etc. that were involved) but the real count is still “unknown”, or still secret, as it was a monumental disaster largely due to communications issues such as transmitter frequencies and hardware breakdowns (Escort and transport ships). The transport ships had a shollow draft and were thought to be safe from German topedo boats. The Germans soon learned to tune their topedos to get around that problem and the transport ships were picked off one by one. One of the transport ships apparently was in dock for repairs and all materiel was loaded onto another transport ship, though there is no offician evidence of that however, there is no official account of the troops that were on the manifest of the docked ship that went “missing”. Another issue, or rather poor decision/communication, was the bombardment of the beach by the Royal Navy was supposed to occur 1 hour before the troops landed. Unfortunately, the beach was bombarded at the same time the troops landed. The exercise, along with US troops playing the enemy on the beach, used live ammunition. Soon after D-Day, the exercise was “forgotten”.