A look at the history of some aspects of ocean studies, including the interaction of the ocean with climate and atmospheric carbon dioxide.
1859 - Greenhouse effect
John Tyndall identifies water vapour and CO2 as gases in the atmosphere that could trap heat rays.
1896 - Prediction of global warming
Swedish scientists Svante Arrhenius and Arvid Högbom realise oceans take up CO2. First prediction of global warming due to CO2 in the atmosphere from industrial emissions. Many scientists disagree.
1897- Carbon cycle model
Thomas Chamberlin creates model of global carbon cycle. The model includes long-term changes in CO2 in oceans and atmosphere.
1906 - Oceans and climate
Thomas Chamberlin realises that ocean temperature and salinity help control climate. He notes that warm oceans give up CO2, cool ones take it up.
1908 - CO2 and acidification
John Gregory realises that an increase in CO2 will mean an increase in carbonic acid in the oceans.
1938 - CO2 and temperature (again)
Guy Callender argues that CO2 levels are rising and causing an increase in global temperature. This revives earlier interest in the topic, but many scientists disagree.
1942 - Deep ocean currents
Harald Sverdrup describes how cold, dense water could sink and cause deep ocean currents, but there is no way of measuring this at the time.
1948 - Carbon cycle can cope
George Hutchinson states that the carbon cycle regulates itself and can cope with increased carbon from the burning of fossil fuels.
1957 - Oceans and CO2
Roger Revelle and Hans Suess work out that the oceans are not taking up enough CO2 to make up for the increased amounts being pumped into the atmosphere by humans.
1960 - Rising CO2 measured
Dave Keeling accurately measures CO2 in the atmosphere on Mauna Loa in Hawaii and detects an annual rise. In this year, CO2 in the atmosphere is 315ppm (parts per million) and the mean global temperature is 13.9°C.
1967 - A new warning
Syukuro Manabe and Richard Wetherald warn again that increasing CO2 in the atmosphere due to human activities will raise global temperatures due to greenhouse effect.
1969 - First satellite measurements
Nimbus-3 satellite starts to provide global temperature measurements.
1978 - Better remote sensing
Nimbus-7 satellite launched, providing global sea surface temperatures and colour. The colour is related to the amount of phytoplankton growing in the sea.
1981 - Warmest year on record
Strong global warming since the 1970s is reported, with 1981 the warmest year on record.
1985 - Not just CO2
Veerabhadran Ramanathan and others announce that other gases, not just CO2, have a role in the greenhouse effect.
1985 - Villach conference
A conference at Villach, in Austria, marks the start of a rapid acceptance of the idea that humans do play a large part in climate change.
1992 - Drifting ocean floats
Russ Davis and Doug Webb develop pop-up drifter floats to measure ocean currents.
1992 - Sea level satellite
TOPEX/Poseidon satellite starts to very accurately measure global sea levels. Changes in sea level reflect changes in temperature, as water expands when warmed and contracts when cool.
1999 - Global remote sensing
NASA’s Terra satellite is launched to collect data monitoring many aspects of Earth’s environment and climate systems.
2000 - First Argo floats
First Argo floats launched to measure currents, temperature and salinity. There are over 3,000 floats by 2010, continuously drifting around the oceans and sending back data via satellites.
2009 - CO2 reaches new high
CO2 in atmosphere reaches 385ppm, with a mean global temperature of 14.4°C – the warmest for hundreds, perhaps thousands, of years. Compare these figures to those recorded in 1960.
2010 - Aquarius satellite
In May, the Aquarius satellite is launched to make the first sea surface salinity measurements from space.
2014 - The Deep South - Te Kōmata o Te Tonga
The Deep South National Science Challenge, hosted by NIWA, sets out to understand the role of the Antarctic and the Southern Ocean in determining our climate and our future environment.
2016 - Hottest year on record
Measurements from NASA and the National Oceanic and Atmospheric Administration put the Earth on track to surpass 2015 as the hottest year on record.