CL
Climate: Past, Present & Future

Climate of the Past

Bomb 14C – a tracer and time marker of the mid-20th century

and July 14, 2021
Bomb 14C – a tracer and time marker of the mid-20th century
Figure 1. Radiocarbon production and three main drivers of the variable atmospheric 14C content (modified figure [4]).

1950 CE is known as the year zero in the so-called ‘BP time scale.’ The BP stands for, “Before Present,” and has its roots in the development and conventions of radiocarbon dating [1]. The radioactive isotope of carbon (14C) with a half-life of 5700 years [2; 3] is a cosmogenic isotope produced in the atmosphere by secondary cosmic rays (SCR). Thermal neutrons, the SCR particle responsible for the ...[Read More]

Detrital zircons: how the age of a resistant mineral can help to reconstruct the climate of the past

May 20, 2021
Detrital zircons: how the age of a resistant mineral can help to reconstruct the climate of the past
Zircon grains of an igneous rock under the incident light microscope (Image Credit: Martin Lindner).

Name of proxy detrital zircon geochronology Type of record provenance proxy Paleoenvironment any sedimentary environment in a geologically diverse and diagnostic area Period of time investigated any Period of the geological timescale of the Earth, during which sedimentary deposits were formed   How does it work? Igneous rocks form through assemblages of minerals crystallising from melt. While ...[Read More]

How humans are influencing climate change and its significance in defining a new geological epoch: the Anthropocene

, and April 26, 2021
How humans are influencing climate change and its significance in defining a new geological epoch: the Anthropocene
Modern atmospheric CO2 increases, driven mainly by human activities, have led to a marked increase in global mean temperatures and rates of sea-level rise in part through melting of ice-sheets. (© C N Waters).

The Anthropocene Working Group (AWG) is the body tasked to propose a formal definition for the Anthropocene as a geological time unit. Join us at the EGU2021 General Assembly on Wednesday 28th April at 14:15-15:00 CEST for a series of presentations on the Anthropocene in session SSP2.6.   The Anthropocene concept Geologists cope with the enormity of 4.5 billion years of Earth history by divid ...[Read More]

Presenting a new European loess map

and March 31, 2021
Presenting a new European loess map

Loess is a silt-sized, aeolian sediment that was produced in large quantities in past geological eras of mid-latitude Europe and Asia, among others (Fig. 1). It is used in Quaternary science to infer about past climatic and environmental conditions. Generally, layers of loess formed during cold and dry periods, while soils formed within/on top the loess during warmer and wetter periods. These soil ...[Read More]