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The ocean holds about 97 percent of Earth's water, yet people have directly seen less than 0.001 percent of the deep seafloor, an area about a tenth the size of Belgium.

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The remaining 3% or so of Earth's water is fresh, and most of that is locked in ice caps, glaciers and groundwater. The seafloor figure comes from a 2025 study in Science Advances, which gathered records of nearly 44,000 dives deeper than 200 metres by crewed submersibles, robots and towed cameras since the 1950s. Sonar can map the shape of the seabed from a ship, but actually seeing it needs lights and cameras a few metres from the bottom, and each dive covers only a narrow strip. The dives were also unevenly spread: about two-thirds of the observations lie within 200 nautical miles of just three countries, the United States, Japan and New Zealand.

Türkçe oku
Dünya'daki suyun yaklaşık yüzde 97'si okyanuslardadır; ama derin deniz tabanının yüzde 0,001'inden azı, yani Belçika'nın onda biri kadar bir alan, bugüne dek doğrudan görülebildi.

Dünya'daki suyun geri kalan yüzde 3 kadarı tatlı sudur ve bunun da çoğu kutup buz örtülerinde, buzullarda ve yer altında hapsolmuştur. Deniz tabanıyla ilgili rakam, Science Advances dergisinde 2025'te yayımlanan bir çalışmadan geliyor: Araştırmacılar 1950'lerden bu yana insanlı denizaltılar, robotlar ve çekili kameralarla 200 metreden derine yapılmış yaklaşık 44.000 dalışın kayıtlarını bir araya getirdi. Sonar, deniz tabanının biçimini gemiden haritalayabilir; ama tabanı gerçekten görmek için ışıkların ve kameraların dibe birkaç metre yaklaşması gerekir, her dalış da yalnızca dar bir şeridi tarar. Üstelik dalışlar dengesiz dağılmış: Gözlemlerin yaklaşık üçte ikisi yalnızca üç ülkenin, ABD'nin, Japonya'nın ve Yeni Zelanda'nın kıyılarından en fazla 200 deniz mili açıktaki sularda yapılmış.

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Background reading: Ocean
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The Wright brothers, bicycle makers from Dayton, Ohio, flew near Kitty Hawk, North Carolina, and that first hop was shorter than the wingspan of a Boeing 747. What followed came fast. In 1919 John Alcock and Arthur Brown flew non-stop across the Atlantic; in 1927 Charles Lindbergh did it alone, from New York to Paris; and in 1947 Chuck Yeager flew faster than sound. Orville Wright died in 1948, nine years before the Soviet satellite Sputnik opened the space age. Yuri Gagarin orbited the Earth in 1961, and in July 1969 Neil Armstrong took a scrap of the 1903 Flyer's wood and fabric with him to the Moon.

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George Orwell used the phrase “cold war” in 1945, and the American journalist Walter Lippmann made it popular in 1947. Because nuclear weapons made open war between the superpowers too dangerous, the rivalry spread into other arenas. After the Soviet Union launched the Sputnik satellite in 1957, the United States passed the National Defense Education Act of 1958 to fund science, maths and language teaching. In 1959, at an American exhibition in Moscow, Vice-President Richard Nixon and the Soviet leader Nikita Khrushchev argued about capitalism and communism in a model kitchen, an exchange remembered as the Kitchen Debate. In 1972 in Reykjavík, the American Bobby Fischer beat the Soviet champion Boris Spassky for the world chess title. The Olympics were boycotted in turn: the United States and many allies stayed away from Moscow in 1980, and most of the Soviet bloc from Los Angeles in 1984.

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