Search results for "Frost"

Dataset of a globally relevant stock of soil nitrogen in the Yedoma permafrost domain

2022

This dataset merges nitrogen data from the Yedoma domain. It includes numerous fieldwork campaigns, which take place since 1998. In total 467 samples from the active layer (seasonally thawed layer), 175 samples from perennially frozen Holocene cover deposits, 479 samples from thermokarst deposits in drained thermokarst, 175 in-situ thawed, diagenetically (anaerobic microbial decomposition possible during unfrozen phase) altered Yedoma deposits (called Taberite), and 917 samples from frozen Yedoma deposits are included. Moreover it includes a NH4+ and NO3- quantification basing on of 658 samples, including 378 data points for NH4+ (active layer, 93; Holocene cover, 108; thermokarst sediment,…

Nitrous oxide fluxes from permafrost regions

2020

This dataset is a synthesis of published nitrous oxide (N2O) fluxes from permafrost-affected soils in Arctic, Antarctic, and Alpine permafrost regions. The data includes mean N2O flux rates measured under field (in situ) conditions and in intact plant-soil systems (mesocosms) under near-field conditions. The dataset further includes explanatory environmental parameters such as meteorological data, soil physical-chemical properties, as well as site and experimental information. Data has been synthesized from published studies (see 'Further details'), and in some cases the authors of published studies have been contacted for additional site-level information. The dataset includes studies publ…

2020

Northern peatlands have accumulated large stocks of organic carbon (C) and nitrogen (N), but their spatial distribution and vulnerability to climate warming remain uncertain. Here, we used machine-learning techniques with extensive peat core data (n > 7,000) to create observation-based maps of northern peatland C and N stocks, and to assess their response to warming and permafrost thaw. We estimate that northern peatlands cover 3.7 ± 0.5 million km2 and store 415 ± 150 Pg C and 10 ± 7 Pg N. Nearly half of the peatland area and peat C stocks are permafrost affected. Using modeled global warming stabilization scenarios (from 1.5 to 6 °C warming), we project that the current sink of atmospheri…

Climate zoning of the Burgundy winegrowing region

2018

As one of the most emblematic wine regions of cool climate terroir viticulture, Burgundy is endowed with a set of very specific natural features suitable to the production of high quality wines, where climate is arguably one of the main factors to profoundly influence vine physiology/phenology and grape composition. These environmental nuances have led to a wide variety of styles in Pinot noir and Chardonnay wines that have been largely acknowledged and appreciated by the international market and vitivinicultural industry. However, individual grape varieties optimum quality is known to be closely related to well-defined climate and geographical ranges. Climate change and global warming late…

Slow Crystallization Kinetics of Poly(vinyl alcohol) in Confined Environment during Cryotropic Gelation of Aqueous Solutions

2006

The gelation kinetics of aqueous solutions of poly(vinyl alcohol) (PVA) during freezing at −13 °C has been investigated with time-resolved small angle neutron scattering. Crystallization of PVA takes place inside an unfrozen liquid microphase that forms in the matrix of ice crystals and follows a first-order kinetics during the early stages and becomes very slow in the later stages with an apparent Avrami exponent lower than 1. Crystallization of PVA at low temperatures is responsible of formation of strong physical gels upon defrosting, provided that the concentration of PVA is higher than a critical value.

Meteorological considerations of grapevine damage due to temperature variations: the 2019 late spring frost and summer heat wave events in Burgundy.

2021

<p><strong><span>Meteorological considerations of grapevine damage due to temperature variations:</span> <span>t</span><span>he 2019 late spring frost and summer heat wave events </span>in Burgundy </strong></p><p>During 2019, <span>the occurrence of two contrasting weather events, a cold snap and a heat wave, caused extensive damage to the vineyards</span> of Northern Burgundy. <span>The late spring cold snap, that </span><span>occurred</span><span&…

Analyse spatiale de l’évolution du risque de gel sur la vigne en Bourgogne-Franche-Comté

2019

The warming undergone by the global climate does not necessarily entail a decrease in frost risk in agriculture/viticulture. Since both plant and climate are likely to evolve under changing environmental conditions, plant vulnerability and the meteorological phenomenon (frost) should be considered jointly when assessing the evolution of frost risk. This study aims at documenting the spatial and temporal frost risk changes in the winegrowing subregions of Bourgogne-Franche-Comté. The period between budburst and the last spring frost occurrence date has been considered as the most vulnerable for grapevines. We considered a plant as being stressed by a frost event when the temperature drops be…

Evolution rétrospective du risque gélif hivernal en climat tempéré suite au réchauffement climatique

2018

Prod 2019-139 BAP POLE EA GEAPSI INRA AGROSUP; National audience; Les modalités du réchauffement climatique sur l’Europe de l’ouest montrent pour les températures une rupture nette en 1987/1988. Deux régimes distincts de température ont eu cours de part et d’autre de cette rupture. Cela offre une opportunité pour évaluer un impact du réchauffement en Bourgogne Franche-Comté. Peu de travaux documentent néanmoins les conséquences du réchauffement hivernal sur la végétation en général et les cultures en particulier. Pourtant, ces dernières années, des travaux suggèrent une augmentation du risque gélif présentée comme un effet paradoxal du réchauffement climatique. En combinant, sur la période …

Le réchauffement climatique diminue-t-il le risque de dégâts par le gel pour les cultures de climat tempéré ?

2014

Does global warming reduce the freezing injury risk to temperate climate crops? Winter crop response to a temperature increase is complex. Recent works point out, for cold climate vegetation, a paradoxical increase in freezing injury in a warming climate. Complementary works are needed to support these results for winter crops in temperate areas. To achieve this goal, five climatic records spanning a fifty years-long period for both daily minimum and maximum temperatures were analyzed with a model predicting frost hardiness and freezing damage for the winter pea crop. The methodological approach was based on three main steps: 1) the climate warming analysis of the 1987/1988 temperature shif…

Évolution retrospective du risque gélif hivernal en climat tempéré suite au réchauffement climatique

2019

An abrupt warming shift of the surface temperature around 1987/1988 has been documented for the western part ofEurope. The arising of two consecutive surface temperature climates offers opportunity to assess the warming impactsover the Bourgogne Franche-Comté area. Few studies focus on the winter warming effects on vegetation and crops. Recentstudies suggest however a paradoxical increase of frost damage in a warming climate. Based on the combination of aMeteo-France climate dataset with a winter frost stress model calibrated for pea, we assessed the winter frost damageevolution along from 1958-2015. Even if frost stress is decreasing at a whole after the temperature shift, subtle and oppos…