6 research outputs found
Validation of meteorological and ground-level ozone WRF-CHIMERE simulations in a mountainous grapevine growing area for phytotoxic risk assessment
Ozone is the most damaging phytotoxic air pollutant to crop yield quantity and quality. This study presents the validation of a simulation with the WRF-CHIMERE modelling system in order to assess the risk of phytotoxicity by tropospheric ozone for an important and characteristic Mediterranean crop, i.e. the grapevine. The study region was the Douro wine region in Portugal, which is characterized by a rugged relief and a Mediterranean climate. The simulation covered a reference grapevine growing season in the Northern Hemisphere (from April to September 2017), during which a particular measuring campaign was also carried out. The validation of the meteorological simulations on a daily and hourly time resolution was performed based on data from three weather stations, namely on temperature, global solar radiation, relative humidity, wind speed and direction values. The ozone phytotoxicity was assessed with data from two measuring stations. A specific grapevine growth parameter based on monitored phenological observations was introduced for ozone stomatal uptake assessment. Concerning meteorology, validation statistics were acceptable and within the range of what has been found in other regional climate modelling simulations. Ground-level ozone-based values were calculated for a better assessment of the phytotoxic risk, in particular cumulative standards for vegetation protection. Stomatal flux estimates were within the range of those measured for the local cultivars in the field campaign when there was not severe water stress limitation. Both field and statistically adjusted model values indicate that considerable areas in the Demarcated Douro Region of Portugal can exceed the critical exposure values for vegetation according to current European legislation standards. Moreover, measured and simulated results indicate an ozone impact on grapevine yield and quality in the target region because the exposure- and flux-based indices exceed the criteria based on current open-top-chamber experimental knowledge.The authors acknowledge the national funds from FCT-Science and
Technology Portuguese Foundation for the doctoral grant of D. Blanco-
Ward (SFRH/BD/139193/2018). Thanks are also due for the financial
support to CESAM (UIDB/50017/2020+UIDP/50017/2020), to FCT/
MEC through national funds, and the co-funding by FEDER within the
PT2020 Partnership Agreement and Compete 2020. The authors also
wish to thank the DOUROZONE project (PTDC/AAG-MAA/3335/2014;
POCI-01-0145-FEDER-016778) for financial support through Project
3599 – Promoting the Scientific Production and the Technological
Development, and Thematic Networks (3599-PPCDT) – and through
FEDER. Thanks are also given to SOGRAPE VINHOS S.A. for facilitating
the collection of surface O3 data and sharing meteorological data at one
of their vineyard fields.info:eu-repo/semantics/publishedVersio
Climate change potential effects on grapevine bioclimatic indices: A case study for the Portuguese demarcated Douro Region (Portugal)
In this work, bioclimatic parameters and indices relevant to the grapevine are estimated for the years 2000 (recent-pat), 2049 (medium-term future) and 2097 (long-term future), based on very high resolution (1 km × 1 km) MPI-WRF RCP8.5 climate simulations. The selected parameters and indices are the mean temperature during the grapevine growing season period (April to October, Tgs), the cumulative rainfall during the grapevine growing season period (Pgs), the Winkler index (WI), the Huglin heliothermic index (HI), the night cold index (CI) and the dryness index (DI). In general, a significant increase in mean temperature during the grapevine growing season period is observed, together with a significant decrease in precipitation. The recent-past WI is associated with the production of high-quality wines; the higher values predicted for the future represent intensive production of wines of intermediate quality. The HI shows the passage of a grapevine growing region considered as temperate-warm to a warm category of higher helio-thermicity. The recent-past CI indicates very cool conditions (associated with quality wines), while in the future there is a tendency for temperate or warmer nights. Finally, DI indicates an increase in water stress considered already high under the recent-past climate conditions. These results point to an increased climatic stress on the Douro region wine production and increased vulnerability of its vine varieties, providing evidence to support strategies aimed to preserve the high-quality wines in the region and their typicality in a sustainable way
Meteorological conditions during the ACLOUD/PASCAL field campaign near Svalbard in early summer 2017
The two concerted
field campaigns, Arctic CLoud Observations Using airborne measurements during
polar Day (ACLOUD) and the Physical feedbacks of Arctic planetary boundary
level Sea ice, Cloud and AerosoL (PASCAL), took place near Svalbard from
23 May to 26 June 2017. They were focused on studying Arctic mixed-phase
clouds and involved observations from two airplanes (ACLOUD), an icebreaker
(PASCAL) and a tethered balloon, as well as ground-based stations. Here, we
present the synoptic development during the 35-day period of the campaigns,
using near-surface and upper-air meteorological observations, as well as
operational satellite, analysis, and reanalysis data. Over the campaign
period, short-term synoptic variability was substantial, dominating over the
seasonal cycle. During the first campaign week, cold and dry Arctic air from
the north persisted, with a distinct but seasonally unusual cold air
outbreak. Cloudy conditions with mostly low-level clouds prevailed. The
subsequent 2 weeks were characterized by warm and moist maritime air from
the south and east, which included two events of warm air advection. These
synoptical disturbances caused lower cloud cover fractions and
higher-reaching cloud systems. In the final 2 weeks, adiabatically warmed
air from the west dominated, with cloud properties strongly varying within the range of the two other periods. Results presented here provide
synoptic information needed to analyze and interpret data of upcoming studies
from ACLOUD/PASCAL, while also offering unprecedented measurements in a
sparsely observed region.</p
Atmospheric and Surface Processes, and Feedback Mechanisms Determining Arctic Amplification: A Review of First Results and Prospects of the (AC)3 Project
Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC)3 project has been established in 2016. It comprises modeling and data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, ship-borne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data
A Consistent Methodology to Evaluate Temperature and Heat Wave Future Projections for Cities: A Case Study for Lisbon
Heat waves are large-scale atmospheric phenomena that may cause heat stress in ecosystems and socio-economic activities. In cities, morbidity and mortality may increase during a heat wave, overloading health and emergency services. In the face of climate change and associated warming, cities need to adapt and mitigate the effects of heat waves. This study suggests a new method to evaluate heat waves’ impacts on cities by considering some aspects of heat waves that are not usually considered in other similar studies. The method devises heat wave quantities that are easy to calculate; it is relevant to assessing their impacts and permits the development of adaptation measures. This study applies the suggested method to quantify various aspects of heat waves in Lisbon for future climate projections considering future mid-term (2046–2065) and long-term (2081–2100) climates under the RCP8.5 greenhouse emission scenario. This is achieved through the analysis of various regional climate simulations performed with the WRF model and an ensemble of EURO-CORDEX models. This allows an estimation of uncertainty and confidence of the projections. To evaluate the climate change properties of heat waves, statistics for future climates are compared to those for a reference recent climate. Simulated temperatures are first bias corrected to minimize the model systematic errors relative to observations. The temperature for mid and long-term futures is expected to increase relative to the present by 1.6 °C and 3.6 °C, respectively, with late summer months registering the highest increases. The number of heat wave days per year will increase on average from 10, in the present climate, to 38 and 63 in mid and long-term climates, respectively. Heat wave duration, intensity, average maximum temperature, and accumulated temperature during a heat wave will also increase. Heat waves account for an annual average of accumulated temperature of 358 °C·day in the present climate, while in the mid and long-term, future climates account for 1270 °C·day and 2078 °C·day, respectively. The largest increases are expected to occur from July to October. Extreme intensity and long-duration heat waves with an average maximum temperature of more than 40 °C are expected to occur in the future climates