H2020Индивидуална стипендия2016–2018

CLIMAGNET · How is the external climatic forcing affected by the Earth’s magnetic field?

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2016-02-01 → 2018-01-31
Финансиране от ЕС: 158 122 €
Участници: 1
Схема: MSCA-IF-EF-ST

Линиите свързват координатора с партньорите.

Накратко на български

Магнитното поле на Земята влияе върху количеството космически лъчи, които достигат до атмосферата и създават определени изотопи. Разбирането на тази връзка помага за по-точното изчисляване на слънчевата активност и възстановяването на миналия климат.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

How is the external climatic forcing affected by the Earth’s magnetic field?

Introduction. The following sentence contained in the publication (in 2013) of the Working Group I of the Intergovernmental Panel on Climate Change (IPCC) summarizes the problem addressed by the CLIMAGNET project: “the radionuclide records reflect not only solar activity, but also the geomagnetic field intensity and effects of their respective geochemical cycles and transport pathways. The corrections for these non-solar components, which are difficult to quantify, contribute to the overall error of the reconstructions”. In other words, the corrections in the rate of production of cosmogenic isotopes by the geomagnetic field (GF) intensity (among other non-solar effects) are not well established, and constitute the focal point of the CLIMAGNET proposal. The connection between GF and the production of isotopes can be briefly described as follows: if the intensity of the GF increases, the density of cosmic rays reaching the atmosphere decreases and, therefore, less rate of production of cosmogenic isotopes is expected. As indicated before, the rate of production is affected by the solar magnetic field, which serves as a basis for developing reconstructions of total solar irradiance provided that corrections for the influence of the GF can be developed. Therefore, a good knowledge of the GF variability is fundamental to appropriately isolate the corrections due to the GF from the solar influence, issue that is not being well considered in the current paleoclimatic reconstructions. To reach this topic, the objectives of CLIMAGNET were divided into two main tasks: Objective 1: Generation of a global paleomagnetic reconstructions for the last millennia using an appropriate weighting scheme of the paleomagnetic data. Objective 2: After obtaining a database of radionuclides, they are used to establish a robust relation between geomagnetic field strength and variation rate of the cosmogenic isotopes. This correlation must be quantified in order to correct the solar forcing during the last millennia.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

The rate of production of cosmogenic isotopes plays an important role in our understanding of past climate variability since they provide information about the solar irradiance related to the Sun’s magnetic field. Having reliable information about past changes in solar irradiance is important for the development of climate model simulations driven by reconstructions of past natural and anthropogenic forcings. One of the sources of uncertainty that affect reconstructions of solar variability is that not only the influence of the solar magnetic field is recorded by the radionuclides; the strength of the Earth’s magnetic field also contributes to modulate the rate of isotope productions. In this context, an appropriate knowledge of the past global geomagnetic field variations is crucial to define the total solar irradiance and hence, to improve reconstructions of external forcing. The past evolution of the geomagnetic field can be recovered from rock samples. The main differences between model predictions are related with the filter applied to the palaeomagnetic data. Up to now, these filters rejected the data according to the measurement and age uncertainties. However, this procedure does not consider the quality of the laboratory protocol or the number of specimens, and hence geomagnetic field predictions might be affected by some unreliable data. Currently, the non-appropriate application of these filters generates spurious variations in the geomagnetic model predictions and these biases are transferred to the reconstruction of the solar variability and consequently to the climatic model simulations. The CLIMAGNET project is aimed to resolve this challenge in two scopes: a) the construction of a global geomagnetic model for the last eight millennia using an appropriate weighting scheme of the palaeomagnetic data; b) the study of the relation between the geomagnetic model predictions and the production rate of cosmogenic isotopes using novel approaches.

Оригинален текст от CORDIS (на английски).

Участници

UNIVERSIDAD COMPLUTENSE DE MADRID · MadridКоординаторИспания