Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Natural climate change may be larger than commonly thought

10.02.2005


A new study of climate in the Northern Hemisphere for the past 2000 years shows that natural climate change may be larger than generally thought. This is displayed in results from scientists at the Stockholm University, made in cooperation with Russian scientists, which are published in Nature on 10 Feb 2005.



The most widespread picture of climate variability in the last millennium suggests that only small changes occurred before the year 1900, and then a pronounced warming set in. The new results rather show an appreciable temperature swing between the 12th and 20th centuries, with a notable cold period around AD 1600. A large part of the 20th century had approximately the same temperature as the 11th and 12th centuries. Only the last 15 years appear to be warmer than any previous period of similar length.

This study builds on an analysis of indirect climate data, such as information from ocean and lake bottoms, ice sheets, caves and annual tree rings. The use of this kind of material to reconstruct climate far back in the past is nothing new in itself. The difference between the new study from previous ones, is the selection of data series and the method used to estimate temperatures from them.


A 1000-year long climate simulation, undertaken (by another research group) with a computer model for the physics of the atmosphere and the oceans, show large similarities with the new reconstruction. The climate in this model is governed by reconstructed variations of solar radiation and the amount of volcanic dust in the atmosphere (which reflects sun-light back into space). The fact that these two climate evolutions, which have been obtained completely independently of each other, are very similar supports the case that climate shows an appreciable natural variability - and that changes in the sun’s output and volcanic eruptions on the earth may be the cause.

This means that it is difficult to distinguish the human influence on climate from natural variability, even though the past 15 warm years are best explained if one includes human influence in the simulations. The new study underscores the importance of including natural climate variability in future scenarios. It is not only the humans that can cause appreciable climate changes - nature does it all the time by itself.

Agneta Paulsson | alfa
Further information:
http://www.eks.su.se

More articles from Earth Sciences:

nachricht Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle
22.06.2018 | Technical University of Denmark

nachricht Polar ice may be softer than we thought
22.06.2018 | Eberhard Karls Universität Tübingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>