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With projected climate change, it is increasingly important to understand the current role of weather in everyday life and how it may change in the future. This paper evaluates two qualitative research approaches for their ability to generate insight into weather-related experiences and everyday practices. As these mundane day-to-day weather interactions often escape memory over time, the paper calls into question the ability of conventional methodological approaches that rely on recall to accurately excavate these events. The research examined serial one-on-one, semi-structured interviews with an adapted short-term focus, and daily diary-photographs. Each approach was applied to one of two Australian cities with sharply contrasting climates - Melbourne and Darwin. Both approaches were able to generate insight into weather-related experiences and practices. However, both presented problems. In interviews, these problems related to retrospective accounts beyond 'yesterday', where physical experience recollections became limited. For diary-photographs, inspiring participants to continually complete and submit contributions proved problematic. I argue that interviews are better for documenting routine practice and generalised experiences, while diary-photographs are better at showing fine-grained detail of physical experiences. Where both aspects are sought, as in this study, a combination is possible. However, using dual methods increases the risk of participant fatigue. [ABSTRACT FROM AUTHOR]

The Amazon River, its huge basin, and the changes in biological processes that are rapidly occurring in this region are unquestionably of global significance. Hence, Global Change Biology is delighted to host a special thematic issue devoted to the Large-scale Biosphere-Atmosphere Experiment in Amazônia (LBA), which is a multinational, interdisciplinary research program led by Brazil. The goal of LBA is no less modest than its subject: to understand how Amazônia functions as a regional entity in the Earth system and how these functions are changing as a result of ongoing changes in land use. This compilation of 26 papers resulting from LBA-related research covers a broad range of topics: forest stocks of carbon (C) and nitrogen (N); fluxes of greenhouse gases and volatile organic compounds from vegetation, soils and wetlands; mapping and modeling land-use change, fire risk, and soil properties; measuring changes caused by logging, pasturing and cultivating; and new research approaches in meteorology to estimate nocturnal fluxes of C from forests and pastures. Some important new synthesis can be derived from these and other studies. The aboveground biomass of intact Amazonian forests appears to be a sink for atmospheric carbon dioxide (CO2), while the wetlands and soils are a net source of atmospheric methane (CH4) and nitrous oxide (N2O), respectively. Land-use change has, so far, had only a minor effect on basin-wide emissions of CH4 and N2O, but the net effect of deforestation and reforestation appears to be a significant net release of CO2 to the atmosphere. The sum of the 100-year global warming potentials (GWP) of these annual sources and sinks of CH4, N2O, and CO2 indicate that the Amazonian forest-river system currently may be nearly balanced in terms of the net GWP of these biogenic atmospheric gases. Of course, large uncertainties remain for these estimates, but the papers published here demonstrate tremendous progress, and also large remaining hurdles, in narrowing these uncertainties in our understanding of how Amazônia functions as a regional entity in the Earth system. [ABSTRACT FROM AUTHOR]

In the first part of this paper existing evidence (mostly from earth and atmospheric sciences) on global climatic changes and their dependence (and effect) upon human action is briefly reviewed. Reference is made to existing major international programmes of research focusing on these climatic changes. The main part of the paper concentrates on the study of global change within the framework of the social sciences. Five psychological characteristics of global environmental change are explained which would account for the human inability to respond adequately without the supportive means of information presentation and processing. Future research on psychological dimensions of global change should explore these in greater detail and study modes of social communication that will become instrumental in implementing such support systems. [ABSTRACT FROM AUTHOR]

Downscaled regional climate simulations for Fiji and Federated States of Micronesia (FSM) from Coupled Model Intercomparison Project 3 (CMIP3) Global Coupled Models (GCMs) are carried out as part of the Pacific Climate Change Science Program (PCCSP) using the CSIRO stretched-grid Conformal Cubic Atmospheric Model (CCAM) for the period 1980-2000. The model simulations are performed at 60 km and at 8 km horizontal resolutions. The higher resolution is chosen to partly resolve the detailed orography of the countries selected, providing insight into the spatial distribution of temperature and precipitation for an individual island that GCMs are unable to represent. The downscaling is carried out in two steps. First, CCAM simulations are run on a global 60 km grid using bias-corrected sea surface temperatures (SST) and sea ice from six CMIP3 GCMs. Three of these 60 km simulations are then further downscaled to 8 km resolution over the two countries. The focus of this paper is validation of these high-resolution simulations against gridded analyses, satellite rainfall climatologies and available station data for rainfall and temperature for the period 1980-2000. The results show that high resolution orography plays an important role in capturing the current climate. The validation demonstrates that the 8 km simulations are capable of realistically depicting the current climate when the topography influences the wind flow and rainfall (Fiji), performing better than both the GCMs and the 60 km downscaled simulations. However, the performance of the 8 km simulations is similar to the GCM and 60 km simulations when topographical features are not present (FSM). [ABSTRACT FROM AUTHOR]

Understanding changes in evaporation rates is expected to be of great importance for water resource planning and management. This paper examines pan evaporation data as an example of the detection and attribution of trends in climate variables. Records of pan evaporation ( Epan), rainfall ( R), radiation ( SR), wind speed ( WS), temperature ( Ta) and humidity ( RH) for the period 1973-2008 were collected from the International Institute of Tropical Agriculture (IITA) in Ibadan, Nigeria. Mann-Kendall trend and Sen's slope tests were performed on the respective meteorological variables and a variability index (VI) was also computed for these. The results showed that annually Epan, SR and WS significantly decrease ( P < 0.001) while R, Ta, and RH showed insignificant increasing trends in the last four decades. Epan and SR decrease at the rate of 8.3 mm year−2 and 37.8 MJ m−2 year−1, respectively. Similar to Epan, SR decreased significantly in all the months ( P < 0.01) and the reduction ranged from 5.1% per decade in March to 9.3% per decade in August. The result of VI showed that the decrease in Epan and other explanatory variables is rather recent. Regression between Epan and other variables indicates that about 30, 15 and 6% of its variance can be explained by SR, WS and VPD (vapour pressure deficit), respectively. The possible roles of dust-haze known as 'harmattan' winds and monsoon clouds in attenuating SR and hence reducing Epan are discussed. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The article presents a study on the climatic fluctuation during the early 20th century. It states that study was guided by review of papers from scientists investigated the climatic fluctuation and its relevance to the continuous climate change. Results show anomaly patterns in the surface air temperature (SAT), sea surface temperature (SST) and related ecosystem that causes anthropogenic climate disturbance attributed to atmospheric circulation.

This paper traces the history of the use of ships' logbooks in climatological studies from the earliest days of the 17th century to the present day. Although early theories concerning global air circulations by Halley and Hadley were based on information gathered by mariners and recorded in their logbooks, it has only been in the last two decades that interest has returned to this important, but long-overlooked, source of climatic information. Attention is drawn to the many advantages offered by logbooks, in particular the long period of time that they collectively cover, their near-global geographic range, the large number of such documents that have survived, and the degree of detailed and reliable record that they provide. Before the mid-19th century, much of the recorded information is noninstrumental in character but its scientific potential is reflected in the variety of approaches and methods that have been used in its analysis and in the equally wide range of outcomes, from databases to synoptic charts and long-time series indices that have emerged from the most recent research. Attention is also drawn to the benefits to be derived from old and more recent instrumental logbook data. As only a small percentage of the tens of thousands of logbooks that have been preserved have thus far been examined, the potential for yet further development is enormous. [ABSTRACT FROM AUTHOR]

Cut-off low pressure systems (COLs) are defined as closed lows in the upper troposphere that have become completely detached from the main westerly current. These slow-moving systems often affect the weather conditions at the earth's surface and also work as a mechanism of mass transfer between the stratosphere and the troposphere, playing a significant role in the net flow of tropospheric ozone. In the first part of this work we provide a comprehensive summary of results obtained in previous studies of COLs. Following this, we present three long-term climatologies of COLs. The first two climatologies are based on the conceptual model of a COL, using European Centre for Medium-range Weather Forecasts (ECMWF) analyses (1958–2002) and National Centers for Environmental Prediction–National Center for Atmospheric Research (1948–2006) reanalysis data sets. The third climatology uses a different method of detection, which is based on using potential vorticity as the physical parameter of diagnosis. This approach was applied only to the ECMWF reanalysis data. The final part of the paper is devoted to comparing results obtained by these different climatologies in terms of areas of preferential occurrence, life span, and seasonal cycle. Despite some key differences, the three climatologies agree in terms of the main areas of COL occurrence, namely (1) southwestern Europe, (2) the eastern north Pacific coast, and (3) the north China–Siberian region. However, it is also shown that the detection of these areas of main COL occurrence, as obtained using the potential vorticity approach, depends on the level of isentropic analysis used. [ABSTRACT FROM AUTHOR]

Understanding of how best to support those most vulnerable to climate stress is imperative given expected changes in climate variability. This paper investigates local adaptation strategies to climate variability, focusing on agricultural decision-making in a communal irrigation scheme in Vhembe District, Limpopo Province, South Africa. Research done through interviews, surveys and participatory methods demonstrates that adaptation strategies within a community are socially differentiated and present differing objectives and priorities. These results highlight the need for intervention and policy that support a heterogeneous response to a wide range of stresses. Evidence for climate change is clear and the need for adaptation is urgent. However, adaptation measures have to be sensitively integrated with ongoing development pathways to ensure they are sustainable and relevant to local priorities. [ABSTRACT FROM AUTHOR]

Recently, the search for evidence of climate‐change impacts has been intense. Long‐term and not so very long‐term data are being examined for evidence of climatic response. Three commonly used methods involve (i) correlation with an ever‐increasing number of climatic variables, (ii) examining trends through time and (iii) a comparison between two points in time. In this paper we provide examples designed to emphasize the need for impassionate and critical examination of findings, the so‐called ‘eclectic’ approach, involving a combination of empirical and conceptual evidence. Copyright © 2005 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

In recent years, Kilimanjaro and its vanishing glaciers have become an ‘icon’ of global warming, attracting broad interest. In this paper, a synopsis of (a) field observations made by the authors and (b) climatic data as reported in the literature (proxy and long-term instrumental data) is presented to develop a new concept for investigating the retreat of Kilimanjaro's glaciers, based on the physical understanding of glacier–climate interactions. The concept considers the peculiarities of the mountain and implies that climatological processes other than air temperature control the ice recession in a direct manner. A drastic drop in atmospheric moisture at the end of the 19th century and the ensuing drier climatic conditions are likely forcing glacier retreat on Kilimanjaro. Future investigations using the concept as a governing hypothesis will require research at different climatological scales. Copyright © 2004 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This paper reviews our understanding of how the effects of the El Niño–southern oscillation (ENSO) might be transmitted from the tropical Pacific Ocean to the Antarctic, and examines the evidence for such signals in the Antarctic meteorological, sea ice, ice core and biological records. Many scientific disciples concerned with the Antarctic require an understanding of how the climatic conditions in the tropical and mid-latitude regions affect the Antarctic, and it is hoped that this review will aid their work. The most pronounced signals of ENSO are found over the southeast Pacific as a result of a climatological Rossby wave train that gives positive (negative) height anomalies over the Amundsen–Bellingshausen Sea during El Niño (La Niña) events. However, the extra-tropical signature can sometimes show a high degree of variability between events in this area. In West Antarctica, links between ENSO and precipitation have shown variability on the decadal time scale. Across the continent itself, it is even more difficult to relate meteorological conditions to ENSO, yet analyses of the long meteorological records from the stations do indicate a distinct switch in sign of the pressure anomalies from positive to negative across the minimum in the southern oscillation index. The oceanic signals of ENSO around the Antarctic are less clear, but it has been suggested that the Antarctic circumpolar wave could be forced by the phenomenon. Ice-core data offer the potential to help in understanding the long-term relationship between ENSO and the climate of the Antarctic, but there are difficulties because of the need to smooth the ice-core data to overcome the mixing of snow on the surface. Nevertheless, analysis of methylsulphonic acid in a South Pole core has shown high variability on ENSO time scales. It is clear that some evidence of ENSO can be found in the Antarctic meteorological and ice-core records; however, many of the relationships tend not to be stable with time, and we currently have a poor understanding of the transfer functions by which such signals arrive at the Antarctic from the tropical Pacific. Copyright © 2004 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

One of the most significant forecasting problems facing meteorologists in the Sydney office of the Australian Bureau of Meteorology is the prediction of the heavy to extreme rainfall amounts that occur on the subtropical north coast of New South Wales (NSW). The significance of the problem lies in the great intensity of the rainfall, the difficulty in predicting the formation, location and duration of the rainfall, and the impacts of flooding on both cities and communities. The forecasting difficulties arise because of the small scales often involved, the range of physical mechanisms responsible and the challenge involved in forecasting events of such short duration. In the case of flash floods, the intense rainfall is typically less than 6 h in duration. Operational numerical weather prediction (NWP) has not shown much success, mainly because of the reasons mentioned above, especially given that computational limitations restrict its model resolutions. In this paper, the synoptic situation is presented for the most severe flash flood on record to affect Coffs Harbour, a city which is located on the NSW mid-north coast. The event, which occurred on the evening of 23 November 1996, is rated approximately as a 1 in a 100-year intensity/duration event. A 25-year climatology subset of flood-producing systems that have affected Coffs Harbour is then presented, and is correlated with the Southern Oscillation Index (SOI). Finally, details are given for a numerical modelling case study of the flash flood. The model results reveal that a very accurate prediction of the amount and the spatial distribution of rainfall amounts can be made for an event of this type. The rainfall totals of over 500 mm in 24 h were accurately forecast using coarse resolution archived operational initial analyses. The success of the predictions is most likely owing to the dominance of large-scale dynamical processes, which were further focused by the steep topography. Copyright © 2000 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Interest in climatic change has never been greater and it is inevitable that the search for periodicities in the climatic record should be a popular means of attempting to unravel at least some of the complexities of the atmospheric system. This paper reviews aspects of the methodologies of spectral analysis and takes the example of the Barcelona precipitation series (1850–1991) to illustrate how both spectral analysis and other statistical analyses can provide information on climatic evolution as expressed through the medium of this one variable. Copyright © 1999 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This month’s issue focuses on the meteorological effects of solar eclipses using data collected in the UK on 20 March 2015 and the USA on 21 August 2017. We begin with Edward Hanna’s examination of data from stations run by amateur enthusiasts, most of them in the Climatological Observers’ Link network. ‘Meteorological effects of the 20 March 2015 solar eclipse over the United Kingdom’ on p. 71 builds on the observations made at Met Office stations, published in Clark ( ) and Hanna et al. ( ). The observations show a high degree of consistency and the reduction in solar radiation had a strong signal in all parts of the UK, even where there were cloudy skies in most southern, as well as many northern and eastern areas. It also adds to the effects reported in this journal, following the eclipse of 11 August 1999 (Hanna, ). Bob Bourton’s short contribution ‘The thermal effects noticed at Heathrow Airport during the partial solar eclipse of 20 March 2015 ‘on p. 81 looks at the effects of the 2015 eclipse at Heathrow Airport. The range of instruments available across the airport and in roads leading to it gives further insight into the temperature and radiation changes during the obscuration of 85% of the sun’s disk in the west of London. On p. 90, we move to the observations made in the USA under the swathe of total or near‐total eclipse on 21 August 2017 in ‘Meteorological impacts of the total solar eclipse of 21 August 2017’, as reported by Stephen Burt. The data from sites run by the National Oceanic and Atmospheric Administration (NOAA, ) are supplemented by observations made by Stephen Burt near Jackson, Wyoming. Because the path of this eclipse crossed much of the USA and could be observed at least partially in all parts of the country, this was probably the best observed eclipse in history. Under clear skies, falls of about 5 degC were seen, accompanied by a fall in wind speed, now known from observations on both sides of the Atlantic to be a significant effect of this short‐duration phenomenon. We also include a seasonally‐appropriate look at the effects of year‐to‐year weather on plants and animals on p. 86. Ian Strangeways’ paper ‘Phenology: plants and animals as meteorological sensors’, gives us an overview of this subject, which used to be one of the activities of the Royal Meteorological Society. He includes the history of its development in the UK, as well as its value in weather science and our knowledge of the effects of changing climate. [ABSTRACT FROM AUTHOR]

Spatial‐resolution errors are inherent in gridded precipitation (P) fields—such as those produced by climate models and from satellite observations—and they can be sizeable when P is averaged spatially onto a coarse grid. They can also vary dramatically over space and time. In this paper, we illustrate the importance of evaluating resolution errors associated with gridded P fields by investigating the relationships between grid resolution and resolution error for monthly P within the Amazon Basin.Spatial‐resolution errors within gridded‐monthly and average‐monthly P fields over the Amazon Basin are evaluated for grid resolutions ranging from 0.1° to 5.0°. A resolution error occurs when P is estimated for a location of interest within a grid‐cell from the unbiased, grid‐cell average P. Graphs of January, July and annual resolution errors versus resolution show that, at the higher resolutions (<3° ), aggregation quickly increases resolution error. Resolution error then begins to level off as the grid becomes coarser. Within the Amazon Basin, the largest resolution errors occur during January (summer), but the largest percentage errors appear in July (winter). In January of 1980, e.g., resolution errors of 29, 52 and 65 mm—or 11, 19 and 24% of the grid‐cell means—were estimated at resolutions of 1.0°, 3.0° and 5.0°. In July of 1980, however, the percentage errors at these three resolutions were considerably larger, that is, 15%, 27% and 33% of the grid‐cell means. Copyright © 2005 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This paper presents a time series analysis of fluctuations in long-term annual mean air temperature series of Turkey, which were tested for non-randomness by the autocorrelation function and subjected to power spectrum methods. Power spectrum estimates are computed for the purpose of finding evidence of a cyclic component within the series. The analysis covered the period of 1930--1995 and included 71 stationsin seven geographical regions. For most of the series, the correlograms revealed no apparent patterns of cyclicity. The arithmetic average of the positive correlation values is about 11 years, and that corresponds well with the sun-spot cycle effect on the temperature values. A further analysis of the series by power spectrum indicated littleevidence for statistically significant differences from the white-noise spectrum. In most cases the spectral densities above the white-noise level tended to peak at frequencies corresponding to 2.4--3.1 and3.3--4.3 years, being particularly pronounced in the east, Mediterranean, central, and south eastern Anatolia regions. The 3.3--4.3-year peaks in the central and south-eastern Anatolia regions were significantly different from white noise at the 95 per cent level. Roughly two groups of regions with different spectral shapes are identified. The coastal regions almost exhibited a white-noise spectrum whereas theinland regions tended to approximate a grey-noise spectrum. [ABSTRACT FROM AUTHOR]