Glaciation and Permafrost Dynamics on the Antarctic Peninsula in the 21st Century

The results of mass balance observations of the ice dome and measurements of the active layer thickness on the Fildes Peninsula, King George (Waterloo) Island, Western Antarctica are presented for the period of 2007 to 2019. The dynamics of the main meteorological parameters affecting the active layer thickness is determined. The numerical experiments based on the mathematical model are performed to determine the effects of various parameters on the active layer thickness. The calculated and measured values of the active layer thickness are compared. The thermal instability of permafrost in the study area in some years with high (above the means) summer air temperature is demonstrated. The climate cooling which started in the region in the recent years has increased the number of years with the positive ice mass balance. However, the positive ice mass balance has not yet become a dominant factor against a background of the negative balance in the previous years.     

Basin organization of nature management for solving hydroecological problems

Presented are the development of the concept and projects of the basin nature management and the organization of their implementation in the whole region using the basin-administrative approach. Based on the multidimensional analysis and forecast of river runoff variations using the artificial neural networks, the typification of catchments is carried out mainly defined by such factors as its area, order of the river, and degree of anthropogenic load. Depending on the hydrological functioning type, the adapted complexes of Hydroecological activities are determined. The need in the integration of the geodata for each river basin with the inherent morphological and process characteristics as well as of the results of Hydroecological monitoring enables to recommend the structure of the database of the basin organization of nature management in the regions of Russia based on the European experience in the river network monitoring in the context of the EU Water Framework Directive and of the creation of the single infrastructure of the spatial data.     

Possibilities to detect trends in spectral UV irradiance

Summary It is investigated how long-term UV trends can be assessed by analysing the longest time series of measured spectral UV irradiance in Europe, which have been started in the early 1990s in Thessaloniki, Greece and Sodankylä, Finland. It can be concluded that both time series do not yet show an unambiguous yearly trend in UV irradiance. The regression lines show no uniform behaviour and vary irregularly in strength and from one solar zenith angle to the next if all sky conditions are analysed. It is emphasised that these findings do not disagree with previous studies, that significant changes in UV irradiance have been observed over Europe especially in spring.Our study introduces a new method to estimate the required time series length for trend detection using the measured time series in combination with model calculations. At Sodankylä, a reduction of the total ozone column of –5.7% per decade has been observed from 1979 to 1998. A positive UV trend due to such conditions may be detected after 12 years at the earliest. For Thessalonki, a decrease in total ozone of –4.5% per decade has been observed. A corresponding increase of UV irradiance should be detectable after 15 years. It should be noted that a constant ozone trend over the whole period had to be assumed for this analysis.Since 1990 there has been a considerable variability of total ozone, but no steady decrease could be observed. Consequently, no general UV increase could be expected due to ozone changes. Even if there was a constant ozone trend over that period it is shown that even the longest European time series of UV irradiance are still too short to show distinct trends. However, this does not imply that no changes have occurred, it only shows that the large natural variability of UV irradiance has so far hindered the identification of unambiguous trends. The only way to find significant and consistent UV trends is the continuation of high-quality long-term measurements of spectral UV irradiance.     

Linking the northern hemisphere sea-ice reduction trend and the quasi-decadal arctic sea-ice oscillation

The nature of the reduction trend and quasi-decadal oscillation in Northern Hemisphere sea-ice extent is investigated. The trend and oscillation that seem to be two separate phenomena have been found in data. This study examines a hypothesis that the Arctic sea-ice reduction trend in the last three decades amplified the quasi-decadal Arctic sea-ice oscillation (ASIO) due to a positive ice/ocean-albedo feedback, based on data analysis and a conceptual model proposed by Ikeda et al. The theoretical, conceptual model predicts that the quasi-decadal oscillation is amplified by the thinning sea-ice, leading to the ASIO, which is driven by the strong positive feedback between the atmosphere and ice-ocean systems. Such oscillation is predicted to be out-of-phase between the Arctic Basin and the Nordic Seas with a phase difference of 3/4, with the Nordic Seas leading the Arctic. The wavelet analysis of the sea ice data reveals that the quasi-decadal ASIO occurred actively since the 1970s following the trend starting in the 1960s (i.e., as sea-ice became thinner and thinner), as the atmosphere experienced quasi-decadal oscillations during the last century. The wavelet analysis also confirms the prediction of such out-of-phase feature between these two basins, which varied from 0.62 in 1960 to 0.25 in 1995. Furthermore, a coupled ice-ocean general circulation model (GCM) was used to simulate two scenarios, one without the greenhouse gas warming and the other having realistic atmospheric forcing along with the warming that leads to sea-ice reduction trend. The quasi-decadal ASIO is excited in the latter case compared to the no-warming case. The wavelet analyses of the simulated ice volume were also conducted to derive decadal ASIO and similar phase relationship between the Arctic Ocean and the Nordic Seas. An independent data source was used to confirm such decadal oscillation in the upper layer (or freshwater) thickness, which is consistent with the model simulation. A modified feedback loop for the sea-ice trend and ASIO was proposed based on the previous one by Mysak and Venegas and the ice/albedo and cloud/albedo feedabcks, which are responsible for the sea ice reduction trend.     

Post-Normal Science and the Global Climate Change Issue

Science has recently faced a new challenge in that it must now provide itsbest knowledge to support the urgent policy-making concerning, e.g., risks oftechnology, environmental pollution, or the climate change. However, thisknowledge unfortunately often can host high uncertainties as the naturalsystems are complex. How to proceed when the facts given by the scientists arediverging and uncertain, while the decision-making is urgent? Funtowicz andRavetz (1992, 1993) argue that in this case traditional `Normal' science(described by Kuhn (1970)) becomes inappropriate and that science shouldbecome `Post-Normal' in order to more effectively cope with these contemporaryproblems. The philosophy, or methodology, of Post-Normal Science is brieflyintroduced and its corelation with the climate change issue, specifically withthe compilation process and summary content of the Second Assessment Report(SAR) from the Working Group I of the Intergovernmental Panel on ClimateChange (IPCC, 1996a), is viewed. It seems that climate science around IPPCcan, to a relatively large extent, be characterized as `Post-Normal'.Moreover, results from some related studies indicate that the elements ofPost-Normal Science in the IPCC have enhanced the problem-solving in theclimate change issue.     

Estimation of water balance components in the Black Sea

Presented are the estimates of precipitation amount and evaporation for the Black Sea basin based on the data of numerical regional reanalysis. The spatial distribution of considered variables is compared with the results obtained before using the method of extrapolation of measurements at the coastal meteorological stations. The computed water balance components of the Black Sea compared with the available literature data are used for obtaining the estimate of the mean water discharge in the Bosphorus.     

Stochastic simulations of the Madden�CJulian oscillation activity

The Madden?CJulian oscillation (MJO) is the most prominent form of tropical intraseasonal variability. This study investigated the following questions. Do interannual-to-decadal variations in tropical sea surface temperature (SST) lead to substantial changes in MJO activity? Was there a change in the MJO in the 1970s? Can this change be associated to SST anomalies? What was the level of MJO activity in the pre-reanalysis era? These questions were investigated with a stochastic model of the MJO. Reanalysis data (1948?C2008) were used to develop a nine-state first order Markov model capable to simulate the non-stationarity of the MJO. The model is driven by observed SST anomalies and a large ensemble of simulations was performed to infer the activity of the MJO in the instrumental period (1880?C2008). The model is capable to reproduce the activity of the MJO during the reanalysis period. The simulations indicate that the MJO exhibited a regime of near normal activity in 1948?C1972 (3.4?events?year^?1) and two regimes of high activity in 1973?C1989 (3.9 events) and 1990?C2008 (4.6 events). Stochastic simulations indicate decadal shifts with near normal levels in 1880?C1895 (3.4 events), low activity in 1896?C1917 (2.6 events) and a return to near normal levels during 1918?C1947 (3.3 events). The results also point out to significant decadal changes in probabilities of very active years (5 or more MJO events): 0.214 (1880?C1895), 0.076 (1896?C1917), 0.197 (1918?C1947) and 0.193 (1948?C1972). After a change in behavior in the 1970s, this probability has increased to 0.329 (1973?C1989) and 0.510 (1990?C2008). The observational and stochastic simulations presented here call attention to the need to further understand the variability of the MJO on a wide range of time scales.     

Institutional Adaptation of Water Resource Infrastructures to Climate Change in Eastern Ontario

Institutional barriers and bridges to local climate change impacts adaptation affecting small rural municipalities and Conservation Authorities (CAs are watershed agencies) in Eastern Ontario (Canada) are examined, and elements of a community-based adaptation strategy related to water infrastructures are proposed as a case-study in community adaptation to climate change. No general water scarcity is expected for the region even under unusually dry weather scenarios. Localized quantity and quality problems are likely to occur especially in groundwater recharge areas. Some existing institutions can be relied on by municipalities to build an effective adaptation strategy based on a watershed/region perspective, on their credibility, and on their expertise. Windows of opportunity or framing issues are offered at the provincial level, the most relevant one in a federal state, by municipal emergency plan requirements and pending watershed source water protection legislation. Voluntary and soon to be mandated climate change mitigation programs at the federal level are other ones.     

Diffusion from a point source in an urban atmosphere

Summary In the present paper, a model for the diffusion of material from a point source in an urban atmosphere is incorporated. The plume is assumed to have a well-defined edge at which the concentration falls to zero. The vertical wind shear is estimated using logarithmic law, by employing most of the available techniques of stability categories. The concentrations estimated from the model were compared favorably with the field observations of other investigators.