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This work presents a novel technique for the determination of soil moisture obtaining 2-D Soil Moisture (SM) information with a single instrument. Both the instrument and the retrieval algorithm used, which is based on inferring the reflection coefficient of the terrain by direct and forward scattering polarimetric measurements of Global Navigation Satellite Systems (GNSS) Signals, are briefly described. Some preliminary results of a field campaign performed on La Pobla de Mafumet (Tarragona, Spain) are presented. This instrument and retrieval algorithm can be used for different applications, such as, an input for the irrigation algorithm (Smart-Irrigation) or forest fire prevention among others. Peer Reviewed

2005

Abstract. This work presents the methane (CH4) and nitrous oxide (N2O) products as generated by the IASI (Infrared Atmospheric Sounding Interferometer) processor developed during the project MUSICA (MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water). The processor retrieves CH4 and N2O with different water vapour and water vapour isotopologues (as well as HNO3) and uses a single a priori data set for all the retrievals (no variation in space and time). Firstly, the characteristics and errors of the products are analytically described. Secondly, the products are comprehensively evaluated by comparisons to the following reference data measured by different techniques and from different platforms as follows: (1) aircraft CH4 and N2O profiles from the five HIAPER Pole-to-Pole Observation (HIPPO) missions; (2) continuous in situ CH4 and N2O observations performed between 2007 and 2017 at subtropical and mid-latitude high-mountain observatories (Izaña Atmospheric Observatory and Jungfraujoch, respectively) in the framework of the WMO–GAW (World Meteorological Organization–Global Atmosphere Watch) programme; (3) ground-based FTIR (Fourier-transform infrared spectrometer) measurements made between 2007 and 2017 in the framework of the NDACC (Network for the Detection of Atmospheric Composition Change) at the subtropical Izaña Atmospheric Observatory, the mid-latitude station of Karlsruhe and the Kiruna polar site.The theoretical estimations and the comparison studies suggest a precision for the N2O and CH4 retrieval products of about 1.5–3 % and systematic errors due to spectroscopic parameters of about 2 %. The MUSICA IASI CH4 data offer a better sensitivity than N2O data. While for the latter the sensitivity is mainly limited to the UTLS (upper troposphere–lower stratosphere) region, for CH4 we are able to prove that at low latitudes the MUSICA IASI processor can detect variations that take place in the free troposphere independently from the variations in the UTLS region. We demonstrate that the MUSICA IASI data qualitatively capture the CH4 gradients between low and high latitudes and between the Southern Hemisphere and Northern Hemisphere; however, we also find an inconsistency between low- and high-latitude CH4 data of up to 5 %. The N2O latitudinal gradients are very weak and cannot be detected. We make comparisons over a 10-year time period and analyse the agreement with the reference data on different timescales. The MUSICA IASI data can detect day-to-day signals (only in the UTLS), seasonal cycles and long-term evolution (in the UTLS and for CH4 also in the free troposphere) similar to the reference data; however, there are also inconsistencies in the long-term evolution connected to inconsistencies in the used atmospheric temperature a priori data.Moreover, we present a method for analytically describing the a posteriori-calculated logarithmic-scale difference of the CH4 and N2O retrieval estimates. By correcting errors that are common in the CH4 and N2O retrieval products, the a posteriori-calculated difference can be used for generating an a posteriori-corrected CH4 product with a theoretically better precision than the original CH4 retrieval products. We discuss and evaluate two different approaches for such a posteriori corrections. It is shown that the correction removes the inconsistencies between low and high latitudes and enables the detection of day-to-day signals also in the free troposphere. Furthermore, they reduce the impact of short-term atmospheric dynamics, which is an advantage, because respective signals are presumably hardly comparable to model data. The approach that affects the correction solely on the scales on which the errors dominate is identified as the most efficient, because it reduces the inconsistencies and errors without removing measurable real atmospheric signals. We give a brief outlook on a possible usage of this a posteriori-corrected MUSICA IASI CH4 product in combination with inverse modelling.

We have implemented a process‐based isoprene emission model in the HadGEM2 Earth‐system model with coupled atmospheric chemistry in order to examine the feedback between isoprene emission and climate. Isoprene emissions and their impact on atmospheric chemistry and climate are estimated for preindustrial (1860–1869), present‐day (2000–2009), and future (2100–2109) climate conditions. The estimate of 460 TgC/yr for present‐day global total isoprene emission is consistent with previous estimates. Preindustrial isoprene emissions are estimated to be 26% higher than present‐day. Future isoprene emissions using the RCP8.5 scenario are similar to present‐day because increased emissions resulting from climate warming are countered by CO2 inhibition of isoprene emissions. The impact of biogenic isoprene emissions on the global O3 burden and CH4 lifetime is small but locally significant, and the impact of changes in isoprene emissions on atmospheric chemistry depends strongly on the state of climate and chemistry.

Wildfires are recurrent natural events that have been increasing in frequency and severity in recent decades. They threaten human lives and damage ecosystems and infrastructure, leading to high recovery costs. To address the issue of wildfires, several activities must be managed and coordinated in order to develop a suitable response that is both effective and affordable. This includes actions taken before (mitigation, prevention, and preparedness), during (response), and after the event (recovery). Considering the available resources and the safety of the involved personnel is a key aspect. This article is a review focused on fire suppression, which comprises actions belonging to the preparedness phase (deployment) and the response phase (dispatching) of the wildfire management scheme. It goes through the models and methodologies that, applying operations research and optimization techniques, address the management of resources to address fire suppression. This article presents a review of the studies published after the last review on the topic in 2017, but also includes some interesting papers before that date. It concludes with some classifying tables and a few conclusions about possible future lines of research.

Recent studies have noted an asymmetrical climate change across Antarctica, with significant warming in West Antarctica and the Antarctica Peninsula, and primarily insignificant trends in East Antarctica. Due to its proximity, variations in the position and intensity of the Amundsen‐Bellingshausen Seas Low (ABSL) are a suspected atmospheric mechanism. Here, we investigate the ABSL to understand its characteristic variability and underlying synoptic‐scale influences, based on three reanalysis data sets. The ABSL is defined as the minimum monthly pressure in the 45°–75°S, 180°–60°W domain. Using this criterion, a significant north‐south and east‐west progression is noted in the climatological (1979–2001 average) ABSL, which is strongly tied to the location of the maximum cyclone system density and minimum cyclone central pressures. More than 550 cyclones a year were identified in the vicinity of the ABSL; during spring, significant trends in their central pressures are noted in the Ross Sea. The implied changes in temperature advection by these stronger systems are consistent with the warming in West Antarctica. The strongest cyclone events (i.e., the ten with the deepest central pressures) also demonstrate a connection to the climatological ABSL, albeit weaker. Moreover, these strong cyclone events are significantly linked to the Southern Annular Mode (SAM), particularly in their annual frequency and location/steering in the summer. This shows that large‐scale forcing, such as from the SAM, may influence the strongest cyclones in the region and could allow for the prediction of such events.

Summary Silviculture is the manipulation of forest stand structure and dynamics to achieve specific forest management objectives. In this paper the proceeding contributions from four State forest services about their silvicultural practices in native forests are introduced and reflected upon in the light of likely future directions in Australian forest management. Increasing ecological knowledge and changing social and economic demands on forests necessitate the continuous development and improvement of silvicultural practices. The role of silviculture in delivering sustainable forest management is discussed and some future challenges in native forest silviculture in a post-Regional Forest Agreement environment are presented. Reconciling management of native forests for biodiversity and for production of timber and non-timber products will be a major task, which may only be achieved through silvicultural planning at the landscape level. Further development and refinement of sustainability indicators will ...

Abstract Background: Volume, biomass and carbon of forest ecosystem are generally estimated using lookup tables or allometric equations known as models. These general equation-based models are usually exclusively based on dimensional measurement such as diameter at breast height (DBH) and/or height, which sometimes makes it difficult to judge applicability of equation to given forest condition or types. It is therefore important to estimate carbon stock and develop models to predict biomass or carbon stock with stratification by categorical variables like crown cover, slope, forest types, etc. Stratification of forest by remote sensing approach while designing forest inventory not only improves the reliability of the estimation but also reduces the cost of measurement and uncertainty in estimation. Taking crown coverage (<25%, 25-50%, 50-75% and >75%) and slope (0-8.5%, 8.5-19%, 19-31% and >31%) as a categorical variable, this study assessed the status of carbon stock and develop a regression model to predict carbon stock for each canopy class of Sal (Shorea robusta) forest in Nepal. DBH and height were measured for trees with more than 7 cm DBH in 82 sample plots (18, 22, 22 and 20 for <25%, 25-50%, 50-75% and >75 % respectively).Results: On average 297 stands per hectare were recorded with 94.80 m3/ha growing stock. Carbon stock was highest for >75% crown cover class (89.83 ton C/ha) and lowest for <25% crown cover class (27.47 ton C/ha) with average 60.41 ton C/ha, where per tree carbon stock was lowest in crown cover class 25-50% (0.16 ton C/tree). TukeyHSD shows that four pairs of crown cover classes have significant difference in carbon stock at 95% confidence interval. However, with increase in slope carbon stock per hectare was decreasing. Regression model with natural logarithm of DBH2 and total tree height (i.e. log transformed polynomial equation) was best fitted for estimation of carbon stock per tree in different crown cover class with adjusted R2 >0.99 and residuals were normally distributed. Conclusions: Adjustment of model (natural logarithm of DBH2 and height) with high accuracy (R2 >0.99) shows the importance of stratification especially by crown cover for accurate estimation of carbon stock for optimization of carbon benefits.