Did We Ever Know What We Were Doing? A Brief History of Weather Forecasting

1. Did We Ever Know What We Were Doing?A Brief History of Weather Forecasting Scott M. Rochette, Ph.D. Associate Professor and Chair Department of the Earth Sciences The College at Brockport

2. Outline • Overview • Earliest Observations • Birth of a Science • Refining Moments • Important Forecasts • The Advent of Technology • What’s Next? • Words to Live By (?)

3. Why is Weather Forecasting So Difficult? • Imagine a rotating spherical envelope 25 miles deep, made of a mixture of gases whose concentrations vary in space and time. • Place it around an astronomical object nearly 8000 miles in diameter, with a bumpy surface. • Tilt the whole system back and forth with respect to its source of heat and light, a nuclear reactor 93 million miles away. • Freeze it at the poles of its axis of rotation and intensely heat it in the middle. • Imagine that the gas mixture continually receives inputs from the surface below, generally calmly but occasionally from violent, highly localized injections. • Subject the whole to tidal forces induced by the sun and a captive satellite. • After watching the system, try to predict its state at one location on the sphere for a period of one to several days in advance. (adapted from Ryan 1982)

4. Words to Live By 1 • Death by burning shall be the punishment for the practice of weather forecasting. (17th Century English law)

5. Earliest Observations 1 • Babylonia, circa 650 BCE: • attempted prediction of short-term weather changes • based on clouds and optical phenomena (halos, etc.)

6. Earliest Observations 2 • Greece, circa 340 BCE: • Aristotle wrote Meteorologica, a four-volume philosophical treatise • included theories regarding the formation of clouds, rain and hail, wind, thunder and lightning, and hurricanes • also addressed astronomy, geography, and chemistry • observations were remarkably acute, despite significant errors: • did not believe wind was air in motion • believed that the west winds are cold because they blow from the sunset • the authority on weather theory for about 2000 years (until WHAM 13)

7. Earliest Observations 3 • China, circa 300 BCE: • astronomers developed calendar • divided the year into 24 festivals, each corresponding to a different type of weather • India, circa 500 AD: • Varahamihira wrote BrihatSamhita, “Great Compilation” • 106 chapters • theorized that rain comes from the sun

8. Birth of a Science 1 • Science implies reproducible results • requires observations and measurements • knowledge to this point based solely on observations • development of weather instruments transformed meteorology into a natural science • First weather ‘instrument?’ • 1450: first ‘hygrometer’ • Cardinal Nicholas de Cusa of Germany • measured the weight change of a bag of wool

9. First Weather Instruments 1 • 1590s: first ‘thermometer’ • Galileo Galilei of Italy • glass spheres filled with alcohol (of slightly different densities) • technically a ‘thermoscope’ (no scale, only registers temperature differences) • first scale would be added about 20 years later

10. First Weather Instruments 2 • 1643: first barometer • Evangelista Torricelli of Italy (student of Galileo) • pump makers noted that they could get water to rise only about 10 meters • filled a glass tube with mercury (density 14x higher than water) and inserted it into a dish • found that the height of the mercury column rose and fell with changes in atmospheric pressure • By allowing atmospheric measurements to be made, ‘meteorology’ became a science

11. Synoptic Weather Reports • One could only do so much with weather information (observed or measured) for a single location • The telegraph (invented in 1837) allowed weather information to be exchanged and collected • Simultaneous (synoptic) weather observations became the basis for understanding and forecasting the weather • ‘Synoptic’ = ‘to view together’

12. What did this do? • Plotting synoptic observations on a map began to show repeating patterns and relationships • storms were known to be associated with low pressure, but no relationship between wind and pressure was established • William Redfield (1831) postulated that winds in hurricanes flow counterclockwise around a low-pressure center (based on a pattern of fallen trees) • James Espy (1841) theorized that air flows toward low pressure and is forced to rise, leading to clouds and precipitation • The establishment of weather maps proved both men correct

13. Weather Maps • First daily weather map series produced by Joseph Henry of the Smithsonian Institution • Started in 1849 with a network of 150 volunteer observers • 10 years later, the network quadrupled in size, including observers in Canada, Mexico, Latin America, and the Caribbean • Precursor to the National Weather Service

14. ‘Murphy’s Winter’ • Some of the first weather forecasts were produced based on theories of planetary or lunar influences (i.e., not based on meteorological observations) • Patrick Murphy of Ireland was one of the more ‘famous’ astrologer-meteorologists • In 1837, he published The Weather Almanack (on Scientific Principles, showing the State of the Weather for every day of the year 1838) • His forecast for 20 January 1838, ‘Fair, probably lowest degree of winter temperature’

15. So How Did He Do? • His forecast for London on 20 January 1838 was correct (temperature at sunrise was -4˚F) • As a result, his almanac was a best-seller, with a run of 45 editions (making him £3,000, a fortune then) • However, an analysis of his 1838 performance showed him to be ‘partially right’ on 188 days, but completely wrong on 197 days (54% of the year) • He published almanacs for the next several years, which made him a decent living • Poor speculating on grain prices cost him most of his fortune

16. Vice-Admiral Robert FitzRoy • Likely best known as the captain of the HMS Beagle (Darwin) • Appointed in 1854 to the position of ‘Meteorological Statist to the Board of Trade,’ in charge of collecting weather data from ships at sea • A storm in 1859 that caused the loss of a clipper ship (450+ lost, 39 survivors) inspired him to create weather charts (similar to those made by Henry) • These charts were used to make predictions of storms, which he called ‘forecasting the weather’ • Daily forecasts began to be published in The Times in 1860 • Likely the first weather forecasts based on meteorological observations

17. A Sad End for FitzRoy • During that time, the standard for forecasting was set by the Royal Observatory • Landmark accomplishments of Newton (1643-1727) and Leibniz (1646-1716) ushered in an era of determinism • “If we can imagine a consciousness great enough to know the exact locations and velocities of all the objects in the universe at the present instant, as well as all forces, . . . It could calculate anything about the past or future from the laws of cause and effect.” (P.-S. Laplace) • Even though they were based on actual meteorological data, FitzRoy’s forecasts were not up to this standard • The damage from astrologer-meteorologists caused distrust of government forecasts by the public and colleagues alike (unlike today, of course) • Forced to abandon his efforts, FitzRoy committed suicide on 30 April 1865

18. Professor Cleveland Abbe • Director of the Cincinnati Observatory • Set up a volunteer observer network similar to that of Joseph Henry • Selected observing equipment and trained observers • Clerks would decode incoming data and plot them on maps • Abbe gave the first official U.S. forecast on 19 February 1871 • He demanded that his team’s forecasts were precisely worded and covered four key elements: temperature, pressure, wind direction, and weather (clouds/ precipitation) • 69% of their forecasts verified

19. Abbe’s Accomplishments • First Chief Scientist of newly formed ‘national weather service’ under U. S. Army Signal Corps (1871-1915) • Advocated for the establishment of time zones in the U.S. and North America (thereby allowing simultaneous weather observations) • Founded Monthly Weather Review in 1872 (still in print!) • Recognized the interdependence of forecasting, climatology, and physical theory (to the chagrin of meteorology students ever since)

20. Early U.S. Weather Map, 1 January 1871 (courtesy of NOAA)

21. Words to Live By 2 • “Probably northeast to southwest winds, varying to the southward and westward and eastward and points between, high and low barometer swapping around from place to place; probable areas of rain, snow, hail, and drought, succeeded or preceded by earthquakes, with thunder and lightning.” (Mark Twain, 1876, on Professor Abbe’s likely weather forecast for New England)

22. Words to Live By 3 • “He who shall predict weather will have no quite life any more, and runs great risk of becoming crazy from nervousness.” • (C. H. D. Buys Ballot, author of the Buys Ballot law)

23. From Empiricism to Determinism • Physical laws govern the motion of fluids (e.g., atmospheric gases) • M. F. Spaaskii (1851), a Russian meteorologist, posed the idea that weather forecasting can be posed as a mathematical problem • Prof. Abbe (1890) published Preparatory Studies of Deductive Methods in Storm and Weather Predictions, which furthered the idea that the laws of physics could be applied to weather prediction • HenrikMohn (Norway), WladimirKöppen (Germany), and Max Margules (Ukraine) postulated that upper-level mechanisms generate energy for storms

24. Words to Live By 4 • “Forecasting is immoral and damaging to the character of a meteorologist.” (Max Margules)

25. Professor VilhelmBjerknes • The pioneer of modern weather forecasting • His 1904 paper provided the basis for numerical weather prediction some 50 years before the first computer model • The future state of the atmosphere can be determined given: • the initial conditions of the atmosphere • appropriate governing equations • Established the Bergen School of Meteorology in 1917 • Son Jacob would also contribute significantly

26. Lewis Fry Richardson • The first person to attempt numerical weather prediction (1922, without a computer) • A Quaker and a pacifist: • he served in WWI as an ambulance driver • developed his theories about NWP during this time • Attempted a forecast of pressure change (from 4 am to 10 am 20 May 1910, near Munich) • six-hour forecast took six weeks • predicted pressure change: 145 mb! • actual pressure change: < 1 mb • greatest range of observed pressure ~100 mb

27. Richardson’s Forecast Factory • Aside from the time problem, Richardson used the full equations • should have neglected small-scale processes • think of a jar filled with rocks of different sizes • He figured about 64,000 people (with hand calculators) would be needed to keep up with the world’s weather • envisioned a giant theatre to house them • the light would shine on ‘areas’ that needed to slow down or speed up • Gave up weather and focused on ‘peaceful’ pursuits • Lived to see the first successful NWP attempt

28. Professor Jacob Bjerknes • Member of the Bergen School • Published a paper in 1922 (at 25!) establishing the Norwegian cyclone model: • extratropical cyclone life cycle • cold, warm, occluded fronts • still used today • Founded the UCLA Department of Meteorology in 1940 • one of five meteorology departments formed that year • MIT, Cal Tech, NYU, University of Chicago

29. Further Advances… • 1930s: Radiosondes make upper-air data available in near-real time • 1930s-WWII: Radar first developed as method for tracking ships and aircraft • WWII: Weather found as ‘noise’ in radar imagery

30. Some Important Forecasts • June 1944: Operation Overlord • Captain John Stagg, RAF • Eisenhower wanted five-day forecasts (!) • Weather requirements: • no fog/low clouds • <60% cloud cover • winds < 20 mph • no high seas • onshore winds < 12 mph

31. D-Day Forecast • 5 June 1944 was originally chosen (moonlight and very low tide) • No-go decision made ~4:30 am on 4 June • Forecast: 6 June would be relatively calm with good visibility, followed by several days of variable weather • Eisenhower, 5 June 1944: “…our little camp was shaking and shuddering under a wind of almost hurricane proportions and the accompanying rain seemed to be traveling in horizontal streaks.” • Storm also prevented German reconnaissance missions • Germans thought invasion unlikely because of the stormy weather on 5 June, and did not foresee the interval of acceptable weather on 6 June • Many problems with invasion, but few due to weather

32. First Tornado Forecast • 20 March 1948: Tinker AFB hit by tornado • 32 aircraft destroyed • several injuries in control tower • $10M+ damages (in 1948 dollars) • Commander ordered a study on tornado-producing thunderstorms • On 25 March 1948, Fawbush and Miller noticed similarities between current conditions and those of 20 March • Hesitantly issued tornado forecast at 2:50 pm • Tornado struck Tinker shortly after 6 pm • $6M damages • NO INJURIES

33. First Weather Broadcasters • E. B. Rideout, 1926 (WEEI radio, Boston, MA) • Jim Fidler, 1934 (WBLC radio, Muncie, IN) • Jim Fidler, 1947 (TV, Dumont Network, later WLWT, Cincinnati)

34. The Age of Computers • 1946: the first electronic computer (ENIAC) is developed at the University of Pennsylvania • That same year, meteorologists pose that the computer should be used for weather forecasting • JuleCharney named director of the Weather Project in 1948, which attempted the first weather forecast by computer

35. The First NWP Model • 1950: the first numerical weather prediction (NWP) model is run on ENIAC • ~30 minutes to make computations • actual forecast took more than 24 hours due to punchcard loading and machine breakdown • Actual 24-h forecast was quite good!

36. The View from Space • 4 October 1957: the Soviet Union launched Sputnik I, the first artificial satellite • 1 April 1960: the U.S. launched TIROS 1, the first successful weather satellite

37. What now? • Technology marches on • faster computers → more (and more accurate) NWP models • started with a single (simple) model in 1950s • number of available models now in double digits • more realistic simulation of large- and small-scale weather features • more (and more complete) weather observations • observations used to be taken by people • automation has improved spatial/temporal coverage • radar and satellite observations improve • one type each of radar and satellite imagery, limited coverage • multiple radars (NWS, TV stations) and radar products • multiple satellites and products cover major fraction of globe • Internet (for better or worse) • world-wide weather information readily available in real-time • provides a better forum for complaints?

38. What’s next? • Science/technology continue to advance weather forecasting • more/faster information transfer via advances in communications technology • more timely, more focused forecasts • ditto for warnings • weather ‘mysteries’ solved? • small-scale weather features and their consequences • formation mechanisms for destructive weather systems • probabilistic weather forecasts • range of possibilities as opposed to deterministic forecasts • accounting for (relative) uncertainty

39. Do we really know what we’re doing?

40. Perhaps we really do…sort of

41. Summary • We have come a long way in the past 2000+ years • Weather forecasting has evolved: • from simple observations… • …through empirical relationships… • …to science-based predictions • Yes, we have more challenges ahead of us • will we overcome them? • wait and see…ask me back in fifty years!