1896 in science

Chemistry

• April – Svante Arrhenius first publishes the "greenhouse law", becoming the first person to predict that emissions of carbon dioxide from the burning of fossil fuels and other combustion processes are large enough to cause global warming through the greenhouse effect.

Earth sciences

• June 15 – The 1896 Sanriku earthquake of 7.2 surface wave magnitude and tsunami in Japan kill 27,000.

Exploration

• August – Conclusion of Nansen's Fram expedition.

Mathematics

• The prime number theorem on the distribution of primes is proved.
• Ernst Schröder announces a proof of the Schröder–Bernstein theorem in set theory.
• Charles L. Dodgson publishes the first part of Symbolic Logic.
• Karl Pearson publishes significant contributions to correlation and regression.

Meteorology

Microbiology

• Ernest Duchesne discovers the antibiotic properties of penicillin as part of his doctoral research, but this is not followed up at this time.
• Ernest Hanbury Hankin discovers the antibiotic properties of what will become identified as bacteriophages.

Physics

• January 12 – H. L. Smith takes the first X-ray photograph.
• March 1 – French physicist Henri Becquerel discovers the principle of radioactive decay when he exposes photographic plates to uranium.
• German physicist Wilhelm Wien derives Wien approximation.

Physiology and medicine

• July – Victor Despeignes pioneers radiation oncology in Lyon.
• Antoine Marfan first describes the symptoms of Marfan syndrome.
• An improved sphygmomanometer, for the measurement of blood pressure, is described by Scipione Riva-Rocci.
• The 12th edition of Richard von Krafft-Ebing's Psychopathia Sexualis introduces the term 'paedophilia'.
• Belgian psychiatrist Jean Crocq publishes .

Technology

• Thomas Ellis Brown produces an innovative design of rolling bascule bridge for Brooklyn.
• Jesse W. Reno produces the first working escalator, installed at Coney Island, Brooklyn.
• Gottlieb Daimler produces the first truck.
• Léon Serpollet invents the flash boiler for the steam car.
• Captain Neville Bertie-Clay, Superintendent of the British Army arsenal at Dum Dum in Bengal, invents an expanding bullet.
• December 11 – William Preece introduces Guglielmo Marconi's work in wireless telegraphy to the general public at a lecture, "Telegraphy without Wires", at the Toynbee Hall in London.

Awards

• Copley Medal: Carl Gegenbaur
• Wollaston Medal for geology: Eduard Suess

Births

• January 3 – Jay Laurence Lush, American livestock geneticist.
• February 2 – Kazimierz Kuratowski, Polish mathematician.
• February 14 – Arthur Milne, English space physicist.
• February 28 – Philip Showalter Hench, American physician, recipient of the Nobel Prize in Physiology or Medicine.
• March 29 – Wilhelm Ackermann, German mathematician.
• April 7 – Donald Winnicott, English child psychiatrist.
• April 14 – Priscilla Fairfield Bok, American astronomer.
• April 30 – Hans List, Austrian inventor.
• May 6 – Rolf Maximilian Sievert, Swedish physicist.
• May 31 – Hilda Lyon, English aeronautical engineer.
• June 1 – Shintaro Uda, Japanese electrical engineer.
• June 7 – Robert S. Mulliken, American physicist, recipient of the Nobel Prize in Chemistry.
• July 16 – Otmar von Verschuer, German eugenicist.
• August 15 – Gerty Cori, Prague-born winner of the Nobel Prize in Physiology or Medicine.

Deaths

• June 23 – Joseph Prestwich, English geologist.
• July 13 – August Kekulé, German organic chemist.
• August 10 – Otto Lilienthal, German aviation pioneer.
• September 18 – Hippolyte Fizeau, French physicist.
• October 21 – James Henry Greathead, British civil engineer.
• October 27 – H. Newell Martin, British physiologist.
• November 3 – Eugen Baumann, German chemist.
• November 22 – George Washington Gale Ferris Jr., American civil engineer, inventor of the Ferris wheel.
• December 10 – Alfred Nobel, Swedish-born inventor.