2013年12月26日

African Humid Periods

Paleoclimate and archaeological evidence tells us that, 11,000-5,000 years ago, the Earth's slow orbital 'wobble' transformed today's Sahara desert to a land covered with vegetation and lakes.



see more deMenocal, P. B. & Tierney, J. E. (2012) Green Sahara: African Humid Periods Paced by Earth's Orbital Changes. Nature Education Knowledge 3(10):12

2011年7月12日

28th IAS Meeting of Sedimentology


I spent my last week in Zaragoza for the 28th IAS annual meeting. It is a nice place, though it is a little hotter than Bremen. Many famous sedimentologists came from all over the world and had a scientific meeting. This is my first international congress and I feel very lucky to take part in it. I got the travel grant from the IAS, Which means a lot to me. I don't have the chance to give a talk, but a poster is OK for me. My pester is about my work in China on differential diagenesis of limestone-marl alternations. Here is my poster and me.

2010年11月14日

2010年11月7日

ITCZ: The Intertropical Convergence Zone

Near the equator, from about 5° north and 5° south, the northeast trade winds and southeast trade winds converge in a low pressure zone known as the Intertropical Convergence Zone or ITCZ. Solar heating in the region forces air to rise through convection which results in a plethora of precipitation. The ITCZ is a key component of the global circulation system.
Weather stations in the equatorial region record precipitation up to 200 days each year, making the equatorial and ITC zones the wettest on the planet. The equatorial region lacks a dry season and is constantly hot and humid.
The migration of the inter-tropical convergence zone (ITCZ) in Africa affects seasonal precipitation patterns across that continent.
ITCZ

Seasonal Migration of the ITCZ in Africa 

Climate change in East Africa

Tropical Africa have a great impact on global climate change. It is influenced by Indian and Atlantic oceans. Comparative with lots of research work in Atlantic oceans, we know little on west Indian ocean around this area. So far, the information that we understand the climate change mostly is from lake sediments.
The East Africa Rift Lakes provide excellent records of paleoclimate from LGM. A lot of work has been done with variety of methods. Many factors has been proposed to explain the region climate change, such as the migration of ITCZ, Indian monsoon,SST of Indian ocean(IOD).
In order to better understand the climate change of East Africa, research from west Indian ocean is necessary.
Picture from http://geology.com/

2010年10月12日

The 2009 version of the International Stratigraphic Chart

The 2009 version of the International Stratigraphic Chart can be downloaded from the following address:http://www.stratigraphy.org/upload/ISChart2009.pdf
I have transformed it into jpeg format.

The 2009 stratigraphic scale has a new definition of Pleistocene.