Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mediterranean hot flush detected after scorching summer

24.09.2003


Sea Surface Temperature around Crete, 31 August 2003


Sea Surface Temperature around Crete, 30 August 2002


Our record-breaking long hot summer heated Europe’s seas as well as the land. Results returned from ESA’s Envisat environmental satellite show Mediterranean waters off Crete around three degrees Celsius warmer than the previous year.

The top image represents sea surface temperature around the island for 31 August 2003, while the second image shows it for 30 August 2002. The brighter the colour the higher the temperature: there is a five-degree difference between the two recorded in waters north of Crete, and a two-to-three degree difference south of Crete. The maximum (bright red) temperature shown in the two images is 25 degrees, the minimum (dark blue) is 16 degrees. Areas in black are either land or covered by cloud.

The data come from Envisat’s Advanced Along Track Radiometer (AATSR), which functions like a space-based thermometer. The instrument records infrared wavelengths of light to calculate sea surface temperature to an accuracy of 0.3 degrees and a spatial resolution of 1 sq km. The images were prepared for ESA by the Rutherford Appleton Laboratory.


"The difference between the two years is a striking demonstration of how variable the climate can be," said Professor David Llewellyn-Jones of University of Leicester, the Principal Investigator for AATSR. "Sea surface temperature is an especially important factor in climate studies because it takes a long time and the transfer of a lot of heat to change it.

"The oceans actually represent an enormous reservoir of heat. It’s not generally realised but they absorb directly the majority of energy radiated from the Sun due to their surface area – covering about 71 per cent of the Earth’s surface. The oceans then transfer heat directly to the atmosphere."

The oceans are a good indicator of possible climate change because they actually store a huge amount of solar heat, and their temperatures are an indication of how much heat they hold. They take much longer to warm up or cool down by comparison to the land or the air, so sea surface temperature records can be used to help identify longer-term climatic trends.

"By themselves, these particular AATSR images just show us is that the climate varies – and that’s nothing new, climate is always fluctuating," said Llewellyn-Jones. "And these are images of two different days in a single locality. Where the AATSR data really become useful are on a larger scale, and over a long time scale."

Earlier versions of the AATSR flew aboard ESA’s previous ERS-1 and ERS-2 spacecraft, so a near-continuous dataset of comparable measurements exists for the last 12 years. And by the time Envisat finishes its mission another five years - or more - will be added to this figure.

"Studying climate models show us we need at least 15 years worth of data to differentiate a definite global temperature increase from the normal variability of climate," explained Llewellyn-Jones. "Preliminary analysis of existing results does indicate a general upward trend, but we will be more certain with more time and more data."

The UK’s Department for Environment, Food and Rural Affairs (DEFRA) and National Environment Research Council (NERC) developed AATSR along with an additional funding contribution from Australia. The instrument can also be used to measure cloud characteristics, land surface cover, plant health and even see forest blazes as they burn. It is one of ten instruments aboard ESA’s Envisat environmental satellite, orbiting the Earth every 100 minutes from 800 km up.

Henri Laur | ESA
Further information:
http://www.esa.int/export/esaSA/SEMRAD0P4HD_earth_0.html

More articles from Earth Sciences:

nachricht Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences

nachricht Sensing shakes
11.03.2019 | University of Tokyo

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

Im Focus: A thermo-sensor for magnetic bits

New concept for energy-efficient data processing technology

Scientists of the Department of Physics at the University of Hamburg, Germany, detected the magnetic states of atoms on a surface using only heat. The...

Im Focus: The moiré patterns of three layers change the electronic properties of graphene

Combining an atomically thin graphene and a boron nitride layer at a slightly rotated angle changes their electrical properties. Physicists at the University of Basel have now shown for the first time the combination with a third layer can result in new material properties also in a three-layer sandwich of carbon and boron nitride. This significantly increases the number of potential synthetic materials, report the researchers in the scientific journal Nano Letters.

Last year, researchers in the US caused a big stir when they showed that rotating two stacked graphene layers by a “magical” angle of 1.1 degrees turns...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Researchers measure near-perfect performance in low-cost semiconductors

18.03.2019 | Power and Electrical Engineering

Nanocrystal 'factory' could revolutionize quantum dot manufacturing

18.03.2019 | Materials Sciences

Long-distance quantum information exchange -- success at the nanoscale

18.03.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>