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Globally, many parts of fire emissions are driven by deforestation. However, few studies have attempted to evaluate deforestation and vegetation degradation fires (DDF) and predict how they will change in the future. In this study, we expanded a fire model used in the Community Land Model to reflect the diverse causes of DDF. This enabled us to differentiate DDFs by cause (climate change, wood harvesting, and cropland, pastureland, and urban land‐use changes) and seasonality. We then predicted the state of fire regimes in the 2050s and 2090s under RCP 2.6 and RCP 6.0 scenarios. Our results indicate that the area affected by global total fires will decrease from the current 452 to 211–378 Mha yr−1 in the 2090s under RCP 6.0 and to 184–333 Mha yr−1 under RCP 2.6, mainly due to socioeconomic factors such as population and economic growth. We also predict that DDF will decrease from the current 73 million hectares per year (Mha yr−1) to 54–66 Mha yr−1 in the 2090s under RCP 6.0 and 46–55 Mha yr−1 under RCP 2.6. The main contributor to these decreases in DDF burned area was climate change, especially the increasing of precipitation. The impact of future land use change on future DDF was similar or slightly lower than present‐day. South America, Indonesia, and Australia were identified as high‐risk regions for future DDF, mainly due to the expansion of wood harvest and pastureland. Appropriate land and fire management policies will be needed to reduce future fire damage in these areas. Plain Language Summary: Global fire activities are affected by climate, land use, and socioeconomic factors. In order to represent changes in future fire activity, we model worldwide burned area with a particular focus on land‐use change and predict future changes. We find that total fires could decrease in the future. The most obvious factor is that socioeconomic change (i.e., population and GDP growth) will decrease future fire activity. Climate change might cause a reduction or increase in total fire. The impact of future land‐use changes on fires is similar to that of present‐day. The land use changes due to wood harvest in tropics and pasture expansion in temperate regions increased regional deforestation or vegetation degradation fires in future. And we expect that these land‐use change will increase fires in South America, Indonesia, and Australia, suggesting the need for adaptation to reduce the impacts of fires in these regions. Key Points: This study estimates present and future burned area using an improved model of deforestation and vegetation degradation firesUntil the 2090s, population and GDP growth may reduce total fires, whereas deforestation and vegetation degradation may increase itSouth America and Australia are predicted to be high‐risk regions, mainly due to wood harvest and pastureland expansion [ABSTRACT FROM AUTHOR]

The bias correction of the General Circulation Model (GCM) outputs has become a routine step that is taken in climate change impact assessments. To responsibly support the decision‐making processes, the climate‐modeling community has been debating about the conceptual requirements that bias‐correction methods should fulfill. Bearing in mind these requirements, we propose to decompose atmospheric variables into three temporal elements that represent the climate mean state, the interannual variability, and the daily variability. This decomposition is aimed at correcting the biases at one time scale without affecting the simulated climate (mean state) trend or the distributional properties at other time scales. The novelty of the proposed approach is, nevertheless, marked by the adjustment of interannual and daily variability that is made by replacing the GCM‐simulated data with synthetic samples drawn from Stable Distributions (SDs) that are fitted to the observed variability. The replacement prevents the transfer of the sampling variability of the calibration period and gives the corrected data the distributional properties of the observed climate. The employment of SDs was motivated by the fact that the climate‐change‐induced changes in the scale, the symmetry, and the frequency of extremes can be measured and applied to the SDs of the observed data. We correct the biases in the GCM‐simulated temperature and precipitation over northern South America using our proposed approach and two other existing ones. Our proposed method is capable of not only preserving the simulated climate trends but also reproducing the observed extremes as well as a more flexible method based on nonparametric distributions. Key Points: We decompose GCM's daily time series into terms that represent the climate mean state, the interannual variability, and the daily variabilityWe replace the modeled daily variability using trend‐preserving synthetic samples that are drawn from stable distributionsThe mathematical properties of stable distributions allow the inclusion of simulated climate change in the correction process [ABSTRACT FROM AUTHOR]

Impacts of the main South American orographic structures (the Andes, the Brazilian Plateau and the Guiana shield) on the regional climate and associated global teleconnection are investigated through numerical experiments in which some of these features are suppressed. Simulations are performed with a ''two-way nesting'' system coupling interactively the regional and global versions of the LMDZ4 atmospheric general circulation model. At regional scale, the simulations confirm previous studies, showing that both the Andes and the Brazilian Plateau exert a control on the position and strength of the South Atlantic convergence zone (SACZ), mainly through their impact on the low-level jet and the coastal branch of the subtropical anticyclones. The northern topography of South America appears to be crucial to determine the leading mode of rainfall variability in eastern South America, which manifests itself as a dipole-like pattern between Southeastern South America and the SACZ region. The suppression of South America orography also shows global-scale effects, corresponding to an adjustment of the global circulation system. Changes in atmospheric circulation and precipitation are found in remote areas on the globe, being the consequences of various teleconnection mechanisms. When the Brazilian Plateau and the Andes are suppressed, there is a decrease of precipitation in the SACZ region, associated with a weakening of the large-scale ascendance. Changes are described in terms of anomalies in the Walker circulation, meridional displacements of the mid-latitude jet stream, Southern annular mode anomalies and modifications of Rossby wave train teleconnection processes. [ABSTRACT FROM AUTHOR]

Climate warming due to human activities will be accompanied by hydrological cycle changes. Economies, societies and ecosystems in South America are vulnerable to such water resource changes. Hence, water resource impact assessments for South America, and corresponding adaptation and mitigation policies, have attracted increased attention. However, substantial uncertainties remain in the current water resource assessments that are based on multiple coupled Atmosphere Ocean General Circulation models. This uncertainty varies from significant wetting to catastrophic drying. By applying a statistical method, we characterized the uncertainty and identified global-scale metrics for measuring the reliability of water resource assessments in South America. Here, we show that, although the ensemble mean assessment suggested wetting across most of South America, the observational constraints indicate a higher probability of drying in the Amazon basin. Thus, over-reliance on the consensus of models can lead to inappropriate decision making.

The measurement of the directional distribution of incident particles was made by using the Real time Radiation Monitoring Device (RRMD)-III placed inside the Space Shuttle STS-84 cruised at an altitude of 400 km and an inclination angle of 51.6 degrees, which are the same as the cruising orbit of the International Space Station (ISS). The directional distributions of incident particles were evaluated over the observed linear energy transfer (LET) range (1-100 keV/micrometers). The pitch angle distribution is also obtained using the geomagnetic model of IGRF-95. The result is roughly in good agreement with the distribution obtained by the VF1-MIN anisotropy model calculation within the present experimental errors, if the shielding distribution is assumed to be uniform.

AFC short interspersed elements (SINEs) were isolated from cichlids from Madagascar, the New World, and Africa and characterized. A new family of long interspersed elements (LINEs), designated the CiLINE2 family, was also isolated from African cichlids, and its consensus sequence was deduced. Upon aligning all of the consensus sequences, we found that the 3'-tail regions of the AFC SINEs and the CiLINE2 family were very similar, providing another example in which a reverse transcriptase responsible for retroposition of SINEs might be contributed in trans by a LINE. Sequence comparisons showed that CiLINE2 in cichlids was closely related to LINE2 in mammals. Furthermore, we found that the 3'-tail sequence shared by the AFC SINEs and CiLINE2 in cichlids was very similar to the 3'-tail sequence shared by the MIR SINEs and LINE2 in mammals, even though the remaining parts of the AFC SINEs and the MIR SINEs were totally different from each other. Thus, the present report not only describes a new pair of SINEs and LINEs with the same 3' tail in cichlids, but also provides a new example of the phenomenon whereby the 3' ends of LINEs with the same genealogical origin can be incorporated into the 3'-end tails of different families of SINEs that have been generated independently in two different lineages during evolution.

The real-time measurement of radiation environment was made with an improved real-time radiation monitoring device (RRMD)-II onboard Space Shuttle STS-79 (S/MM#4: 4th Shuttle MIR Mission, at an inclination angle of 51.6 degrees and an altitude of 250-400km) for 199 h during 17-25 September, 1996. The observation of the detector covered the linear energy transfer (LET) range of 3.5-6000 keV/micrometer. The Shuttle orbital profile in this mission was equivalent to that of the currently planned Space Station, and provided an opportunity to investigate variations in count rate and dose equivalent rate depending on altitude, longitude, and latitude in detail. Particle count rate and dose equivalent rate were mapped geographically during the mission. Based on the map of count rate, an analysis was made by dividing whole region into three regions: South Atlantic Anomaly (SAA) region, high latitude region and other regions. The averaged absorbed dose rate during the mission was 39.3 microGy/day for a LET range of 3.5-6000 keV/micrometer. The corresponding average dose equivalent rates during the mission are estimated to be 293 microSv/day with quality factors from International Commission on Radiological Protection (ICRP)-Pub. 60 and 270 microSv/day with quality factors from ICRP-Pub. 26. The effective quality factors for ICRP-Pub. 60 and 26 are 7.45 and 6.88, respectively. From the present data for particles of LET > 3.5keV/micrometer, we conclude that the average dose equivalent rate is dominated by the contribution of galactic cosmic ray (GCR) particles. The dose-detector depth dependence was also investigated.