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The relative importance of the processes responsible for the annual cycle in the upper-ocean heat content in the Peru Current, in the southeastern tropical Pacific, was diagnosed from an oceanic analysis dataset. It was found that the annual cycle of heat content is forced mainly by insolation. However, the ocean dynamical processes play an important role in producing different regional budget characteristics. In a band 500 km from the coast of Peru, the annual heat content changes in this region are relatively large and can be approximated as sea surface temperature (SST) changes in a fixed-depth mixed layer. The annual cycle of the albedo associated with low-level clouds enhances the annual cycle in insolation, which explains the relatively strong annual cycle of heat content. These clouds, to a large extent, act as a feedback to SST, but a small additional forcing, which is proposed to be cold air advection in this paper, is needed to explain the fact that the maximum cloudiness leads the lowest SST by around a month. Ocean dynamics is important closer to the coast, where upwelling acts partly as damping of the heat content changes and forces it to peak earlier than farther offshore. In a band farther to the southwest, locally wind-forced thermocline motions, which become shallower (deeper) in the warm (cool) season, partially cancel the effect of net surface heat fluxes, whose annual cycle is comparable to that in the region previously mentioned, producing a relatively small annual cycle of heat content. The local forcing appears to be associated with the annual meridional displacements of the South Pacific anticyclone. The annual cycle in SST is also relatively small, which is probably due to the changes in the temperature of the water entrained into the mixed layer associated with the thermocline motions, but also to a mixed layer deeper than that closer to the coast. [ABSTRACT FROM AUTHOR]

Abstract: Climatic change is one of the most important issues of present times. Unlike the greenhouse gases, which have a predominantly warming effect, atmospheric aerosols could either warm or cool the atmosphere depending upon the size, distribution and optical properties. Of all the climatic elements, temperature plays a major role in detecting climatic change brought about by urbanization and industrialization. This paper, therefore, attempts to study temporal variation in temperature over Pune city, India, during the period 1901–2000. The long-term change in temperature has been evaluated by Mann–Kendall rank statistics and linear trend. The analysis reveals significant decrease in mean annual and mean maximum temperature. This decrease in temperature is more pronounced during the winter season, which can be ascribed to a significant increase in the amount of suspended particulate matter (SPM) in the ambient air during the last decade. On the contrary, monsoon season shows warming. This warming can be attributed to a significant increase in the low cloud amount. [Copyright &y& Elsevier]

Abstract: The objective of this paper is to synthesize the large literature recording changing patterns of precipitation in the observed data, thus indicating that climate change is already a reality. Such a synthesis is required not only for environmental researchers but also for policy makers. The key question is the broad picture at major regional and continental levels. Some interesting conclusions for this survey are emerging. For example, the review shows increased variance of precipitation everywhere. Consistent with this finding, we observe that wet areas become wetter, and dry and arid areas become more so. In addition, the following general changing pattern is emerging: (a) increased precipitation in high latitudes (Northern Hemisphere); (b) reductions in precipitation in China, Australia and the Small Island States in the Pacific; and (c) increased variance in equatorial regions. The changes in the major ocean currents also appear to be affecting precipitation patterns. For example, increased intensity and frequency of El Niño and ENSO seem associated with evidence of an observed “dipole” pattern affecting Africa and Asia, although this time series is too short so far. But the changing pattern calls for renewed efforts at adaptation to climate change, as the changing precipitation pattern will also affect the regional availability of food supply. [Copyright &y& Elsevier]

A review of the present status of the global warming science is presented in this paper. The term global warming is now popularly used to refer to the recent reported increase in the mean surface temperature of the earth; this increase being attributed to increasing human activity and in particular to the increased concentration of greenhouse gases (carbon dioxide, methane and nitrous oxide) in the atmosphere. Since the mid to late 1980s there has been an intense and often emotional debate on this topic. The various climate change reports (1996, 2001) prepared by the IPCC (Intergovernmental Panel on Climate Change), have provided the scientific framework that ultimately led to the Kyoto protocol on the reduction of greenhouse gas emissions (particularly carbon dioxide) due to the burning of fossil fuels. Numerous peer-reviewed studies reported in recent literature have attempted to verify several of the projections on climate change that have been detailed by the IPCC reports. The global warming debate as presented by the media usually focuses on the increasing mean temperature of the earth, associated extreme weather events and future climate projections of increasing frequency of extreme weather events worldwide. In reality, the climate change issue is considerably more complex than an increase in the earth’s mean temperature and in extreme weather events. Several recent studies have questioned many of the projections of climate change made by the IPCC reports and at present there is an emerging dissenting view of the global warming science which is at odds with the IPCC view of the cause and consequence of global warming. Our review suggests that the dissenting view offered by the skeptics or opponents of global warming appears substantially more credible than the supporting view put forth by the proponents of global warming. Further, the projections of future climate change over the next fifty to one hundred years is based on insufficiently verified climate models and are therefore not considered reliable at this point in time. [ABSTRACT FROM AUTHOR]

Abstract: Currently there is an increasing research activity in the area of climate extremes because they represent a key manifestation of non-linear systems and an enormous impact on economic and social human activities. Our understanding of the mean behavior of climate and its ‘normal’ variability has been improving significantly during the last decades. In comparison, climate extreme events have been hard to study and even harder to predict because they are, by definition, rare and obey different statistical laws than averages. In this context, the motivation for this paper is twofold. Firstly, we recall the basic principles of Extreme Value Theory that is used on a regular basis in finance and hydrology, but it still does not have the same success in climate studies. More precisely, the theoretical distributions of maxima and large peaks are recalled. The parameters of such distributions are estimated with the maximum likelihood estimation procedure that offers the flexibility to take into account explanatory variables in our analysis. Secondly, we detail three case-studies to show that this theory can provide a solid statistical foundation, specially when assessing the uncertainty associated with extreme events in a wide range of applications linked to the study of our climate. To cite this article: P. Naveau et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Climate change policies are informed by contributions from public, private and civil society organisations at a range of scales from the local to the global. Such policy formation has come to be termed multilevel governance. Transnational networks of local authorities are an emerging feature of multilevel governance and they have been heralded as a means to improve the implementation of climate change policy on the ground. However empirical evaluation of these transnational climate change networks is geographically limited and no research examining their impact in Ireland has been conducted. In response this paper considers the significance of European climate change networks within Ireland's climate change strategy. It concludes that these formal transnational networks have had limited impact to date due to ongoing negotiations about the politics of scale and responsibility with respect to climate change policies in Ireland. [ABSTRACT FROM AUTHOR]

It has been identified that, long-term climatic changes (Pleistocene ice ages) have been caused by periodic changes in the distribution of incoming solar radiation due to the variations in the earth’s orbital geometry, that is the tilt, precision of equinoxes and eccentricity which take place with periodicity ranging from 41 to 9508 thousand years. However, it has been considered that the major potential mechanism of climate change over the next few hundred years will be anthropogenic green house gas warming up. A number of gases that occur naturally in the atmosphere in small quantities are known as ”greenhouse gases. Water vapour, carbon dioxide, ozone, methane, and nitrous oxide trap solar energy in much the same way as do the glass panes of a greenhouse or a closed automobile. This natural greenhouse gases effect has kept the earth’s atmosphere some 30°C hotter, than it would otherwise be, making it possible for humans to exist on earth. Human activities, however, are now raising the concentrations of these gases in the atmosphere and thus increasing their ability to trap energy. The enhanced greenhouse gas effect is expected to cause high temperature increase globally (1–3.5°C) and this will lead to an increase in precipitation in some regions while other regions will experience reduced precipitation (±20%). The impact of expected climate change will affect almost all the sectors of the human endeavor. However, the major purpose of this project is to evaluate the impact of climate change on hydrology and water resources and establish the appropriate adaptation strategies for Swaziland. The impact of climate change on hydrology and water resources will be evaluated using General Circulation Model results (rainfall, potential evapotranspiration, air temperature, etc.) as inputs to a rainfall runoff model. Water use in all the sectors of the human endeavor will be determined in order to establish the water availability given different climate change scenarios. Three catchments have been selected for this exercise. This paper therefore, presents the background information, objectives and significance of the study, literature review, methodology, data collection and processing. [Copyright &y& Elsevier]

As the international community debates long-term strategies to address global warming, the issue is one of increasing concern for small island developing states. Collectively, these countries account for less than 1% of greenhouse gas emissions, yet their vulnerabilities are particularly high. This paper reviews international efforts including a regional effort on the part of 12 Caribbean countries to address this issue. For many countries and especially countries of the Caribbean and other small island developing states, vulnerabilities already exist and will only be exacerbated by accelerated global warming. Dealing with global environmental change will require good, reliable information to monitor change and assess the physical and economic impact of that change. It also will require an institutional and managerial framework that incorporates dynamic change into individual and collective decision-making processes. Small island developing states must be active players affecting long-term solutions to climate change. In the interim, targeted investments to address high priority vulnerabilities are likely to lead to no-regrets outcomes with high environmental and economic benefits. [ABSTRACT FROM AUTHOR]

Five years down the road from Kyoto, the Protocol that bears that city’s name still awaits enough qualifying ratifications to come into force. While attention has been understandably focussed on the ratification process, it is time to begin thinking about the next steps for the global climate regime, particularly in terms of a deeper inclusion of developing countries’ concerns and interests. This paper begins doing so from the perspective of the developing countries. The principal argument is that we need to return to the basic principles outlined in the Framework Convention on Climate Change in searching for a north–south bargain on climate change. Such a bargain may be achievable if we can realign the policy architecture of the climate regime to its original stated goals of sustainable development. [Copyright &y& Elsevier]

The process of translating scientific information into timely and useful insights that inform policy and resource management decisions, despite the existence of uncertainties, is a difficult and challenging task.Policy-focused assessmentis one approach to achieving this end. It is an ongoing process that engages both researchers and end-users to analyze, evaluate and interpret information from multiple disciplines to draw conclusions that are timely and useful for decision makers. This paper discusses key characteristics of a policy-focused assessment process, including (1) ongoing collaboration between the research, assessment, and stakeholder communities; (2) a focus on stakeholder information needs; (3) multidisciplinary approaches; (4) use of scenarios to deal with uncertainties; and (5) evaluation of risk management options. We illustrate the particular challenge to assessors of providing the specific types of insights stakeholders need to effectively influence policy decisions. And we discuss the role that assessment can play in formulating an agenda for future research. Examples from the U.S. National Assessment of “The Potential Consequences of Climate Variability and Change for the United States” are used to illustrate a policy-focused assessment process. For many of the participants, the first U.S. National Assessment was an extraordinary learning experience about how to develop better ways of conducting assessments. [ABSTRACT FROM PUBLISHER]

In the nine years since its establishment in 1988, the Intergovernmental Panel on Climate Change (IPCC) has attempted to walk the tightrope of being scientifically sound and politically acceptable. This paper investigates how the IPCC has evolved over two assessment cycles. It provides an in-depth examination of important characteristics of the IPCC process including the peer review mechanism, participation of developing countries, and its interactions with the intergovernmental negotiation process on climate change. [ABSTRACT FROM AUTHOR]

Abstract: Conceptual models linking climate change with fluctuations in fish population abundances are based on how cyclic patterns in air–sea interactions influence pelagic food web dynamics. The effect of changing mixed layer dynamics on phytoplankton light and nutrient exposure is a prominent focal point in the overall mechanism. The Extended Reconstruction (ER) of Sea Surface Temperature (SST) version one (ERSSTv1) and version two (ERSSTv2) monthly time series from 1854 to 2003, interpreted with the aid of a historically based global Nitrate Depletion Temperature (NDT) climatology, provide a qualitative tool for examining relative temporal and spatial patterns in nitrate availability in normal salinity areas of the world ocean. After an analysis of local NDT variability at four time series stations demonstrated temporal stability compared to SST, [SST–NDT] as a Nitrate Availability Index (NAI) was calculated for April (boreal spring or austral fall) and October (boreal fall and austral spring) for the whole ERSSTv1 data set and for selected years of the ERSSTv2 data set using the global NDT climatology. The more negative the NAI difference, the greater the expected surface nitrate. The more positive the NAI difference, the greater the intensity of temperature stratification between the surface and the nitracline and thus the less likely that nitrate mixed to the surface. The records from April and October both showed that decreased nitrate availability, defined by both smaller negative NAI differences and larger positive NAI differences, generally though not universally occurred throughout the 20th century in association with global warming. The greatest decreases in nitrate availability occurred in two warming events in the time periods 1909–1937 and 1977–present in the Northern Hemisphere and 1926–1937 and 1950–1990 in the Southern Hemisphere. Different areas of the world ocean were affected in each warming event. Prominent exceptions in the ERSSTv1 analysis where 20th century nitrate availability actually increased in at least one season were in western parts of the South Indian, the North Pacific, the equatorial Pacific, the South Pacific, the North Atlantic, and the South Atlantic and in eastern parts of the South Pacific and South Atlantic. The ERSSTv2 analysis also showed increased 20th century nitrate availability in the eastern subarctic Pacific. The nitrate availability trends resulting from the present analysis agree with various literature reports on regional changes in plant nutrient availability, on increased occurrences of harmful algal blooms often associated with dinoflagellates that are better able to access subsurface nitrate pools, and on decadal changes in marine fisheries. They also raise concerns about the resilience of historical patterns of pelagic community structure and function in response to a warming trend continuing into the 21st century. [Copyright &y& Elsevier]

An introduction to the journal is presented in which the editor discusses papers published within the issue about different extreme climate events.

The article offers information on climate change and ozone layer publications in New Zealand. These publications include the topics on preparing for and adapting to climate change and understanding and taking action on climate change. The reference numbers for these publications which were released on January 2007 are also mentioned. It is also forwarded that other publications and background information on climate change are available on the New Zealand Climate Change web site. This encompasses information sheets, economic analysis reports, general publications, and technical working papers.

Invasive species pose a major, yet poorly addressed, threat to sustainable forestry. Here we set forth an interdisciplinary science strategy of research, development, and applications to reduce this threat. To spur action by public and private entities that too often are slow, reluctant, or unable to act, we recommend (a) better integrating invasive species into sustainable forestry frameworks such as the Montréal Process and forest certification programs; (b) developing improved cost estimates to inform choices about international trade and pest suppression efforts; and (c) building distributed information systems that deliver information on risks, identification, and response strategies. To enhance the success of prevention and management actions, we recommend (a) advancing technologies for molecular identification, expert systems, and remote sensing; (b) evolving approaches for ecosystem and landscape management; and (c) better anticipating interactions between species invasions and other global change processes. [ABSTRACT FROM AUTHOR]