Mechanisms of midlatitude cross-tropopause transport using a potential vorticity budget approach

[ 1] A potential vorticity (PV) budget method has been used to attribute vertical transport across the near-tropopause ( 1 PVU surface) in extratropical weather systems to radiative, latent heating and cooling, and mixing processes. Sources and sinks of PV due to nonconservative processes are calculated online and advected as passive tracers. There is reasonable agreement between the spatial distribution of transport determined from the PV budget method and the transport across the 1 - 2 PVU zone from a passive tracer and trajectories, but different aspects of exchange can be diagnosed with each method. Stratosphere-to-troposphere transport occurred in the broad upper level PV anomalies and was attributed mainly to latent heating and cooling processes; troposphere-to-stratosphere transport occurred toward the tail of a PV filament and in a ridge region and was attributed mainly to radiative processes. The contribution of mixing processes to transport was comparatively small. Using the PV budget method, the domain integrated exchange across the 1 PVU surface was from stratosphere to troposphere, and the magnitude of 1 x 10(15) kg over a 2 day winter integration in a large North Atlantic domain is consistent with stratosphere-troposphere exchange calculations from other studies. This exchange arises from an approximate balance between the dominant stratosphere-to-troposphere transport due to latent heating and cooling processes and troposphere-to-stratosphere transport due to radiative processes. The direction of transport across the tropopause in a fold was found to be critically dependent on the PV surface considered to represent the tropopause.

Cross-hemispheric transport of Central African biomass burning pollutants: Implications for downwind ozone production

Pollutant plumes with enhanced concentrations of trace gases and aerosols were observed over the southern coast of West Africa during August 2006 as part of the AMMA wet season field campaign. Plumes were observed both in the mid and upper troposphere. In this study we examined the origin of these pollutant plumes, and their potential to photochemically produce ozone (O3) downwind over the Atlantic Ocean. Their possible contribution to the Atlantic O3 maximum is also discussed. Runs using the BOLAM mesoscale model including biomass burning carbon monoxide (CO) tracers were used to confirm an origin from central African biomass burning fires. The plumes measured in the mid troposphere (MT) had significantly higher pollutant concentrations over West Africa compared to the upper tropospheric (UT) plume. The mesoscale model reproduces these differences and the two different pathways for the plumes at different altitudes: transport to the north-east of the fire region, moist convective uplift and transport to West Africa for the upper tropospheric plume versus north-west transport over the Gulf of Guinea for the mid-tropospheric plume. Lower concentrations in the upper troposphere are mainly due to enhanced mixing during upward transport. Model simulations suggest that MT and UT plumes are 16 and 14 days old respectively when measured over West Africa. The ratio of tracer concentrations at 600 hPa and 250 hPa was estimated for 14–15 August in the region of the observed plumes and compares well with the same ratio derived from observed carbon dioxide (CO2) enhancements in both plumes. It is estimated that, for the period 1–15 August, the ratio of Biomass Burning (BB) tracer concentration transported in the UT to the ones transported in the MT is 0.6 over West Africa and the equatorial South Atlantic. Runs using a photochemical trajectory model, CiTTyCAT, initialized with the observations, were used to estimate in-situ net photochemical O3 production rates in these plumes during transport downwind of West Africa. The mid-troposphere plume spreads over altitude between 1.5 and 6 km over the Atlantic Ocean. Even though the plume was old, it was still very photochemically active (mean net O3 production rates over 10 days of 2.6 ppbv/day and up to 7 ppbv/day during the first days) above 3 km especially during the first few days of transport westward. It is also shown that the impact of high aerosol loads in the MT plume on photolysis rates serves to delay the peak in modelled O3 concentrations. These results suggest that a significant fraction of enhanced O3 in mid-troposphere over the Atlantic comes from BB sources during the summer monsoon period. According to simulated occurrence of such transport, BB may be the main source for O3 enhancement in the equatorial south Atlantic MT, at least in August 2006. The upper tropospheric plume was also still photochemically active, although mean net O3 production rates were slower (1.3 ppbv/day). The results suggest that, whilst the transport of BB pollutants to the UT is variable (as shown by the mesoscale model simulations), pollution from biomass burning can make an important contribution to additional photochemical production of O3 in addition to other important sources such as nitrogen oxides (NOx) from lightning.

Ownership Advantages in Cross-border Real Estate Development: Some Evidence from European Markets

Drawing upon European industry and country case studies, this paper investigates the scope and drivers of cross-border real estate development. It is argued that the real estate development process encompasses a diverse range of activities and actors. It is inherently localised, the production process is complex and emphermal, and the outputs are heterogeneous. It analyses a transactions database of European real estate markets to provide insights into the extent of, and variations in, market penetration by non-domestic real estate developers. The data were consistent with the expectation that non-domestic real estate developers from mature markets would have a high level of market penetration in immature markets. Compared to western European markets, the CEE real estate office sales by developers were dominated by US, Israeli and other EU developers. This pattern is consistent with the argument that non-domestic developers have substantial Dunning-type ownership advantages when entering immature real estate markets. However, the data also suggested some unexpected patterns. Relative to their GDP, Austria, Belgium, Denmark, Sweden, Netherlands and Israel accounted for large proportions of sales by developers. All are EU countries (except Israel) with small, open, affluent, highly traded economies. Further, the data also indicate that there may be a threshold where locational disadvantages outweigh ownership advantages and deter cross-border real estate development.

An analysis of the determinants of cross-border real estate development flows

This paper investigates the scale and drivers of cross-border real estate development in western and central and eastern Europe (CEE). Drawing upon existing literature on the integration of international real estate markets, we make some inferences on expected patterns of cross-border real estate development from this literature review. The paper draws upon a transactions database in order to assess the penetration of national markets by international real estate developers. The determinants of cross-border transaction flows are modeled as a function the range of economic and real estate variables. Whilst western European markets tend to be dominated by local developers, much higher levels of market penetration by international real estate developers are found in the less mature markets of central and eastern Europe. Empirical modelling based on gravity model specifications reveal the importance of size of the economies, distance between countries, extent of globalization and EU membership as significant determinants of cross-border real estate development flow.

The effects of cross-border and cross-industry mergers and acquisitions on home-region and global multinational enterprises

We examine the effects of international and product diversification through mergers and acquisitions (M&As) on the firm's risk–return profile. We identify the rewards from different types of M&As and investigate whether becoming a global firm is a value-enhancing strategy. Drawing on the theoretical work of Vachani (Journal of International Business Studies, 22 (1991), pp. 307−222) and on Rugman and Verbeke's (Journal of International Business Studies, 35 (2004), pp. 3−18) metrics, we classify firms according to their degree of international and product diversification. To account for the endogeneity of M&As, we develop a panel vector autoregression. We find that global and host-region multinational enterprises benefit from cross-border M&As that reinforce their geographical footprint. Cross-industry M&As enhance the risk–return profile of home-region firms. This effect depends on the degree of product diversification. Hence there is no value-enhancing M&A strategy for home-region and bi-regional firms to become ‘truly global’.

Cross-border capital flows into real estate

This study investigates the determinants of cross-border capital flows into direct real estate markets. In particular, it investigates how existing institutional, regulatory and real estate specific barriers affect cross-border real estate inflows and outflows in a sample of 24 developed and emerging countries, and whether investors seek out targets with lower barriers and regulatory arbitrage. We do not find evidence of significant cross-border institutional or regulatory arbitrage in the real estate market. However, real estate market liquidity is found to be the most important driver of cross-border flows. While many of the institutional barriers included in this analysis do not appear to impact the level of real estate inflows significantly, their presence tends to suppress real estate capital outflows to other countries. Overall, easy access to financial markets, a good economic environment and transparent real estate markets may enhance real estate outflows, while returns and the macroeconomy are found to enhance domestic real estate investment.

Privatisation and cross-border electricity trade: from internal market to European Supergrid?

he perspective European Supergrid would consist of an integrated power system network, where electricity demands from one country could be met by generation from another country. This paper makes use of a bi-linear fixed-effects model to analyse the determinants for trading electricity across borders among 34 countries connected by the European Supergrid. The key question that this paper aims to address is the extent to which the privatisation of European electricity markets has brought about higher cross-border trade of electricity. The analysis makes use of distance, price ratios, gate closure times, size of peaks and aggregate demand as standard determinants. Controlling for other standard determinants, it is concluded that privatisation in most cases led to higher power exchange and that the benefits are more significant where privatisation measures have been in place for a longer period.

The persistence of distance: a gravity model of European cross-border real estate development flows

Purpose – This paper aims to investigate the scale and drivers of cross-border real estate development in Western Europe and Central and Eastern Europe. Design/methodology/approach – Placing cross-border real estate development within the framework of foreign direct investment (FDI), conceptual complexities in characterizing the notional real estate developer are emphasized. Drawing upon a transaction database, this paper proxies cross-border real estate development flows with asset sales by developers. Findings – Much higher levels of market penetration by international real estate developers are found in the less mature markets of Central and Eastern Europe. Analysis suggests a complex range of determinants with physical distance remaining a consistent barrier to cross-border development flows. Originality/value – This analysis adds significant value in terms of understanding cross-border real estate development flows. In this study, a detailed examination of the issues based on a rigorous empirical analysis through gravity modelling is offered. The gravity framework is one of the most confirmed empirical regularities in international economics and commonly applied to trade, FDI, migration, foreign portfolio investment inter alia. This paper assesses the extent to which it provides useful insights into the pattern of cross-border real estate development flows.

The impact of cross-border real estate investment on commercial real estate capitalisation rates

This study examines the impact of foreign real estate investment on the US office market capitalization rates. The geographic unit of analysis is MSA and the time period is 2001-2013. Drawing upon a database of commercial real estate transactions provided by Real Capital Analytics, we model the determinants of market capitalization rates with a particular focus on the significance of the proportion of market transactions involving foreign investors. We have employed several econometric techniques to explore the data, potential estimation biases, and test robustness of the results. The results suggest statistically significant effects of foreign investment across 38 US metro areas. It is estimated that, all else equal, a 100 basis points increase in foreign share of total investment in a US metropolitan office market causes about an 8 basis points decrease in the market cap rate.

An examination of cross-border strategies in banking

The paper examines the process of bank internationalisation and explores how banks become international organisations and what this involves. It also makes an assessment of the significance of their international operations and determines whether banks are truly global organisations. The empirical data are based on the 60 largest banks in the world and content analysis is used to categorise the information into the eight international strategies of Atamer, Calori, Gustavsson, and Menguzzato-Boulard [Internationalisation strategies. In R. Calori, T. Atamer, & P. Nunes (Eds.), The dynamics of international competition – from practice to theory, strategy series (pp. 162–206). London: Sage (2000)] and Bryan, Fraser, Oppenheim, and Rall [Race for the World strategies to build a great global firm. Boston, MA: Harvard Business School Press (1999)]. The findings suggest that the majority of banks focus on countries or geographic regions in which they have some sort of cultural or economic affinity. Moreover, apart from a relatively small number of very large banks, they are international rather than truly global organisations.