Identifying Meta-QTLs for Stay-Green in Sorghum

To develop resilient crops it is necessary to understand the underlying genetics of climatic response. A strong association between stay-green and post-flowering drought tolerance in Sorghum has been established. Being a complex quantitative trait, Quantitative Trait Loci (QTL) mapping experiments of stay-green in Sorghum have been frequently performed. The objective of the current study was to find consensus genomic regions that control stay-green by integrating the QTLs mapped in previous studies. Meta-QTL analysis was performed to summarize 115 QTLs projected on the consensus map. The analysis generated 32 Meta-QTL regions within which candidate gene (CG) identification was undertaken. 7 candidate genes were identified using the markers tightly linked to the Meta-QTLs. The results from this study will facilitate future attempts aiming to improve and understand drought tolerance in Sorghum.

Speleothem record of mild and wet mid-Pleistocene climate in northeast Greenland

The five interglacials before the Mid-Brunhes Event (MBE) [c.430 thousand years (ka) ago] are generally considered to be globally cooler than those post-MBE. Inhomogeneities exist regionally, however, which suggest that the Arctic was warmer than present during Marine Isotope Stage (MIS) 15a. Using the first speleothem record for the High Arctic, we investigate the climatic response of northeast Greenland between c.588 and c.549 ka ago. Our results indicate an enhanced warmth of at least +3.5°C relative to the present, leading to permafrost thaw and increased precipitation. We find that δ18O of precipitation was at least 3‰ higher than today and recognize two local cooling events (c.571 and c.594 ka ago) thought to be caused by freshwater forcing. Our results are important for improving understanding of the regional climatic response leading up to the MBE and specifically provide insights into the climatic response of a warmer Arctic.

Modelling the Present Global Terrestrial Climatic Response Due to a Chicxulub-Type Asteroid Impact

A Chicxulub-like asteroid event occurs, on average, approximately every ~27 to 200 million years. Therefore, such an event could happen presently. Here, we simulate the climatic anomalies it may cause with respect to the current conditions, assuming the same target geology of carbonates and evaporates and a 1 Gt release of sulphate gases. We used a thermodynamic model, including water vapor, cloudiness (by greenhouse and albedo effects), and cryosphere feedback to calculate aerosol cooling. We found that it took nearly 4.5 years for solar radiation to recover its preimpact value—during the first year practically no solar radiation reached the surface. Recovery of the temperature took more than 45 years. The lowest temperatures occurred between 1.5 and 5 years after the impact, being the coldest at −14 °C below the preimpact temperature. July surface temperature anomalies occurred 1.5 years after the impact, becoming one of the largest, compared to preimpact temperatures. Most continents showed temperature anomalies of −45 °C. The least cold places were the polar regions with temperature anomalies between approximately −5 and 0 °C. As for the most remarkable climatic effect, we found that, for ~6 years, the ice extended over almost all the ocean surface and, after ~25 years, it covered nearly half of the surface, remaining so for beyond 45 years. The continental ice remained without reduction beyond 45 years. Sixty years after the impact, the surface oceanic and continental fractions covered by ice were 0.52 and 0.98, respectively. We also modeled the effect of smaller quantities of sulfur released after asteroid impacts, concluding that an instantaneous, large climatic perturbation attributed to a loading range may lead to a semi-permanent shift in the climate system.

The Climatic Response of Tree Ring Width Components of Ash (Fraxinus excelsior L.) and Common Oak (Quercus robur L.) from Eastern Europe

This paper aims to develop the first differentiated (earlywood—EW, latewood—LW, and total ring width—RW) dendrochronological series for ash (Fraxinus excelsior L.) and oak (Quercus robur L.) trees from the Republic of Moldova, and to analyze their climatic response and their spatio-temporal stability. For this, 18 ash and 26 oak trees were cored from the Dobrușa protected area, Republic of Moldova, Eastern Europe, and new EW, LW, and RW chronologies were developed for ash and oak covering the last century. The obtained results showed that the RW and LW have a similar climatic response for both species, while EW is capturing interannual climate variations and has a different reaction. The analyses performed with monthly climatic data revealed a significant and negative correlation with the mean air temperature and a significant and positive correlation with precipitation and the Standardized Precipitation-Evapotranspiration Index (SPEI) for both ash and oak. The temperature during the vegetation period has a strong influence on all tree-ring components of ash, while for oak the strong correlation was found only for LW. The positive and significant correlation between LW and RW with precipitation for both species, suggests that ash and oak are sensitive to the hydrological component and the precipitation is the main tree growth-limiting factor. Despite the significant correlation with precipitation and temperature for the whole analyzed period, the 25-year moving correlation analyses show that they are not stable in time and can switch from positive to negative or vice versa, while the correlation with SPEI3 drought index, which is a integration of both climatic parameters, is stable in time. By employing the stability map analysis, we show that oak and ash tree ring components, from the eastern part of the Republic of Moldova, have a stable and significant correlation with SPEI3 and scPDSI drought indices from February (January) until September, over the eastern part of Europe.

On the dependency of simulated volcanically-forced variability to model configuration

<p>Several uncertainties affect the simulation of the climatic response to strong volcanic forcing by coupled climate models, which primarily stem from model specificities and intrinsic variability. To better understand the relative contribution of both sources of uncertainties, the Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP) has been initiated as part of the CMIP6 protocol. VolMIP has defined a coordinated set of idealized volcanic perturbation experiments with prescription of the same volcanic forcing and coherent sampling of initial conditions to be performed to the different participating coupled climate models. However, as the VolMIP effort focuses on comparison across different models, an open question remains about how different configurations of the same model affect the comparability of results.</p><p> Here, we present first results of CMIP6 VolMIP simulations performed with the MPIESM1.2 in two resolutions. The low resolution (LR) configuration employs an atmospheric resolution of T63 (~200 km), and nominal ocean resolution of 1.5°. The high resolution (HR) configuration employs twice of the horizontal resolution of its atmospheric component (T127 ~100 km)   with a spontaneously generated QBO, and an eddy-permitting ocean resolution of  0.4°.</p><p>In this contribution we illustrate results from the volc-pinatubo experiments, which focus on the assessment of uncertainty in the seasonal-to-interannual climatic response to an idealized 1991 Pinatubo-like eruption, and from the volc-long experiments, which are designed to investigate the long-term dynamical climate response to volcanic eruptions. We compare responses of different climate variables, e.g. near-surface air temperature, precipitation and sea ice on global and regional scale.  Special emphasis will be placed on the volcanic impact on the tropical hydrological cycle.</p>

The climatic response of thermally integrated photovoltaic–electrolysis water splitting using Si and CIGS combined with acidic and alkaline electrolysis

Real data modelling of the hydrogen yield using different PV and electrolyzer combinations with hourly climatic data for mid-European climate.