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This research effort assesses the performance of the High Energy Laser End-to-End Operational Simulation (HELEEOS) Climatological C2n optical turbulence model. Path-integrated C2n values of two HELEEOS optical turbulence pro les at 3 distinct operational altitudes are compared to values determined from measured thermosonde data. HELEEOS desert and mid-latitude sites are selected from the Extreme and Percentile Environmental Reference Tables (ExPERT) database for comparison to the thermosonde data. Statistical equivalence of the two datasets is determined through a Design of Experiments (DOE) factorial test to within 80% confidence. The HELEEOS profiles are shown to be equivalent to the thermosonde data for a 500 m boundary layer profile. Deterministic values of the 80% confidence intervals are established. The HELEEOS optical turbulence model is used as the input turbulence model for wave optics simulations. Long-term spot size measurements show that HELEEOS outperforms empirical turbulence models by as much as 17%. Recommendations are made to improve the HELEEOS graphical outputs and reference tables.

Major sources of social archives for paleoclimatology in East and Southeast Asia include ancient annals and chronicles, instrumental records from government, military or missionary bodies, and private records such as diaries. Records are rich but scattered and of inconsistent quality, often requiring different forms of cross-validation and homogenization from those in the Western world. This article discusses these source types.

In the global-warming debate, definitive answers to questions about ultimate causes and effects remain elusive. In Global Warming: Myth or Reality?, Marcel Leroux seeks to separate fact from fiction in this critical debate from a climatological perspective. Beginning with a review of the dire hypotheses for climate trends, the author describes the history of the 1998 Intergovernmental Panel on Climate Change (IPCC) and many subsequent conferences. He discusses the main conclusions of the three IPCC reports and the predicted impact on global temperatures, rainfall, weather and climate, while highlighting the mounting confusion and sensationalism of reports in the media. After taking a hard look at the reality of the greenhouse effect, the 'evidence' from climate models, and the models' limitations, Leroux postulates alternate causes of climate change and analyzes the trends for global temperatures, rainfall patterns, and sea level. He poses the 'heretical' question if warming may be considered a benefit in some regions. Finally Leroux suggests a number of priorities for climatologists to better understand processes of climate change, to integrate them into climate models, and to predict accurately future changes in climate. This timely and controversial book lays out the scientific case of the sizable skeptical scientific community who challenge the accepted wisdom

This presentation is authored by: Beggs, Helen, Chunxue Yang, Vincenzo Artale, Bruno Buongiorno Nardelli, Vincenzo De Toma, Francesca Elisa Leonelli, Salvatore Marullo, Andrea Pisano, Rosalia Santoleri, Xu Li, Boyin Huang, Prasanjit Dash, Jorge Vazquez, Simon Good, Chongyuan Mao and the IC Task Team (2020) and it was presented at the 21st GHRSST Science Team Meeting, Virtual Meeting hosted by EUMETSAT, 1st – 4th June 2020. Resources: About the TASK TEAM ON CLIMATOLOGY AND L4 INTER-COMPARISON (IC TT): https://www.ghrsst.org/about-ghrsst/task-teams/ghrsst-climatology-and-l4-inter-comparison-task-team-ic-tt/ Proceedings of the GHRSST Science Team Meeting 2020: https://zenodo.org/record/4626734 ; The GHRSST Project Office is funded by the European Union (European Commission, EUMETSAT, Copernicus). Web: http://www.ghrsst.org Follow us on Twitter: https://twitter.com/GHRSST

Although some politicians, pundits, and members of the public do not believe it, global warming predictions by mainstream climate scientists have been remarkably accurate while those made by climate deniers have not. And if mainstream global warming predictions continue to prove correct, the window of opportunity to prevent a climate catastrophe is quickly closing. This book is the first to illustrate the accuracy--and inaccuracy--of global warming predictions made by mainstream climate scientists and by climate contrarians from the 1970s to the present day. Written in simple, non-technical language that provides an accessible explanation of key climate science concepts, the book will appeal to general audiences without previous knowledge about climate science. Author Dana Nuccitelli, an environmental scientist and risk assessor, discusses some key climate discoveries dating back to the 19th century and debunks myths such as the idea that climate scientists and climate models have grossly over-predicted global warming. He addresses recent findings of a 97-percent consensus in the peer-reviewed scientific literature that humans are causing global warming--a nearly unanimous agreement that formed in the early 1990s and has grown through the present day. Nuccitelli also discusses what the future climate might look like if current trends continue unabated, and what we as a global society need to do to prevent a climate catastrophe

The overview of studies of waterspouts over the world is presented. The most well-known schematic models of the waterspouts formation are given. The main factors of waterspouts genesis above the water surface are identified. Open access data about waterspouts formed on the Earth from 2000 to 2022 are collected and analyzed. Three main areas of waterspouts formation are highlighted as the following: Mediterranean Sea, Gulf of Mexico and adjacent Atlantic, Great Lakes. The frequency of occurrence of waterspouts in countries with the largest number of cases of their annual registration (USA, Italy, Greece, Russia, Turkey) has been estimated. Well known data about waterspouts characteristics derived from direct and remote measurements are summarized. A conceptual scheme of their structure is described. Waterspouts in Russia are analyzed. Statistics about cases of their registration off the Russian Black Sea coast are given. Map with places of Black Sea waterspouts landfalls is created.

Abstract. Large hail (greater than 2 cm in diameter) can cause devastating damage to crops and property and can even cause loss of life. Because hail reports are often collected by individual countries, constructing a Europe-wide large-hail climatology has been challenging to date. However, the European Severe Storm Laboratory's European Severe Weather Database provides the only pan-European dataset for severe convective-storm reports. The database is comprised of 62 053 large-hail reports from 40 CE to September 2020, yet its characteristics have not been evaluated. Thus, the purpose of this study is to evaluate hail reports from this database for constructing a climatology of large hail. For the period 2000–2020, large-hail reports are most prominent in June, whereas large-hail days are most common in July. Large hail is mostly reported between 13:00–19:00 local time, a consistent pattern since 2010. The intensity, as measured by maximum hail size, shows decreasing frequency with increasing hailstone diameter and little change over the 20-year period. The quality of reports by country varies, with the most complete reporting being from central European countries. Thus, results suggest that despite its short record, many indications point to the dataset representing some reliable aspects of the European large-hail climatology, albeit with some limitations.