Solar signals in sea level pressure and sea surface temperature

We investigate solar cycle signals in 150 years of Sea Level Pressure (SLP) and Sea Surface Temperature (SST) data, using multiple regression analysis. We detect a solar signal in both SLP and SST in the North Pacific during DJF, similar to that found by Van Loon et al. (2007) but of smaller magnitude. We do not, however, identify the signal they found in the tropics. Our results do not support mechanisms for a solar influence on climate directly involving tropical SSTs. We have used different reconstructions of total solar irradiance to investigate the sensitivity of the results. The series of Krivova & Solanki and Foster give similar results to those acquired using sunspot number but the Hoyt & Schatten solar index sometimes produces different results because of mixing of the solar signal with a long-term trend. Using different approaches Labitzke and van Loon (1992) and Camp and Tung (2007), arrived at different results for a solar influence on winter stratospheric polar temperatures and its relationship to the quasi-biennial oscillation (QBO) in tropical stratospheric zonal winds. We show that these differences appear different largely because of their choices of QBO height. We also show that the effect of the QBO (30, 40 or 50 hPa) combined with solar activity reveals a clear signal in polar annular modes expressed in SLP. We show that the nature of ENSO was different before 1950s (and after1997): this may affect any solar influence. Other authors have suggested that tropical circulations were different during the intervening period. Such observation may have implications relating to the sun, tropical circulation and climate change. During 1958-1997, omission of ENSO from regression gives false warming (cooling) signal of higher (lower) solar on SST in tropics. Such analysis, accompanied by our observation that the years of peak annual sunspot number used by van Loon et al. (2007) generally falls a year or more in advance of the maximum of the smoothed DSO, provides coherence to some apparently conflicting findings. Finally, an atmosphere-ocean coupling process, (mainly involving the Pacific Ocean) is proposed to account for the solar influences. This coupling appears to be disturbed during the later half of the 20th century, probably due to climate change

Incentives for Green R&D in a Dirty Industry under Price Competition

In an oligopolistic framework with price competition, we examine the effect of abatement taxes, as well as emission caps on the incentives for adopting a green technology. We identify two new strategic effects, namely the relative efficiency effect, and the competition softening effect, that affect the incentive for green R&D. Under an abatement tax, R&D incentives increase whenever the new technology is non-drastic, and the demand function is either approximately linear, or not too elastic. Another sufficient condition is that the market size be sufficiently large. With emission caps, the result depends on how green the new technology is.Abatement tax, emission caps, environmental policy, green R&D, price competition.

Mergers, pollution and environmental policy

We examine the impact of abatement taxes on the pollution level in a duopoly framework with endogenous market structure. We demonstrate that an increase in abatement taxes could trigger a regime-switch from Cournot competition to merger, as well as from merger to Cournot competition. The nature of this switch is critically dependent on the nature of merger costs. However, in either case, this may cause the pollution level to increase.Mergers, pollution, abatement tax, endogenous market structure

Re-visiting the Porter Hypothesis

We provide a new formulation of the Porter hypothesis that we feel is in the spirit of the hypothesis. Under this formulation we find that the Porter hypothesis need not hold universally, and identify conditions under which it may or may not hold. We first consider the case where the abatement costs associated with a technology is exogenously given. In that case stricter government regulation increases the incentive for adopting the new technology if the old and the new technologies are relatively environmentally friendly to begin with. We then consider the case where the abatement costs associated with a technology is endogenously given. We show that the Porter hypothesis is likely to hold if the new technology is significantly more efficient in production compared to the old technology, or if both the technologies are relatively efficient in production. Whereas if both the technologies are relatively inefficient, then the Porter hypothesis is unlikely to go through. Thus, under the appropriate conditions, the Porter hypothesis may hold even in a static framework.Porter hypothesis, environmental policy, R&D

Joint venture instability: a life cycle approach

Joint ventures represent one of the most fascinating developments in international business. In the last few decades, the rate of joint venture formation has accelerated dramatically. Nowadays joint ventures are much more widespread and occur in industries like telecommunications, biotechnology etc. At the same time, however, it must be noted that joint ventures are very unstable. In this paper we survey the phenomenon of joint venture instability. We draw on the relative recent theoretical literature on joint venture instability to provide a unified explanation of joint venture life-cycles, formation, as well as breakdown. Further, we do this for both research oriented, as well as production joint ventures.Joint ventures; formation; breakdown; synergy; moral hazard; learning

Combating COVID-19 crisis and exploring heat-based simple solutions

Covid-19 pandemic affected whole of the world taking many lives and impacting the economy and mental health severely. Exit pathways via vaccination though ignited optimism initially but attenuated by the emergence of several new variants which are less sensitive to vaccines. Considering emergency situations, some urgent, simple heat-based solutions for the initial stages of the disease were also proposed at the beginning of pandemic and further elaborated here. Solutions were proposed based on science as follows: exploring results of statistical analyses on the global transmission of COVID-19; observed temperature-dependent behaviours of similar category viruses; temperature-based clinical trial experiments with similar category viruses; successful clinical trial experiments with heat-based intervention for COVID-19 patients; and finally, biological mechanism/response in human bodies to heat-based solution for COVID-19 from medical doctor's perspective. Solutions proposed are practically without side effects, can be even practised in own home and there is no vested interest involved

Contrasting different techniques for identifying the role of Sun and the El Niño Southern Oscillation on Indian Summer Monsoon Rainfall

A solar influence on Indian Summer Monsoon (ISM) rainfall, identified in previous studies using the method of solar peak year compositing, may not be robust and can be influenced by other factors such as ENSO and trends. Compositing fails in the Southern Hemisphere where a trend in Sea Level Pressure is clear. Solar peak years suggested –ve NAO features with significant signal around the Azores High, whereas trough years suggest +ve features of NAO with significant influence around the Icelandic Low. Regression analysis, which takes into account variations across the whole solar cycle rather than just the min/max fails to detect any direct solar influence on ISM but the spatial pattern of the Southern Oscillation has changed in recent decades with major changes around Australia. Through the Indian Ocean Dipole, this may have had an impact on ISM rainfall. During the second half of last century, the local north south Hadley circulation, as manifest in the NAO in the northern Hemisphere and the IOD in the southern hemisphere, may have played an important role in modulating the ISM. We discuss these potential indirect connections between the solar cycle and monsoon rainfall, which are different since the 1950s

Addressing Abrupt Global Warming, Warming Trend Slowdown and Related Indian Summer Monsoon Features in Recent Decades

This study addresses abrupt global warming and a slowdown thereafter that happened in recent decades. It separated the role of anthropogenic CO2 led linear trend to that from natural factors (volcano and the sun). It segregates a period 1976–1996 where two explosive volcanic eruptions occurred in active phases of strong solar cycles and also the period covers two whole solar cycles. That same period coincided with abrupt global warming. This study suggests that domination of a particular type of ENSO, the Central Pacific (CP) type ENSO and related feedback from water vapour played a crucial role. A plausible mechanism was proposed that could be triggered by explosive volcanos via a preferential North Atlantic Oscillation (NAO) phase. It modulates the CP ENSO via extratropical Rossby wave and affects the Aleutian Low. From that angle, it is possible to explain the disruption of ENSO and Indian Summer Monsoon teleconnection during the abrupt warming period and how it recovered subsequently afterward. Interestingly, individual models and also the CMIP5 model ensemble fails to agree with the observation. This study further explores important contributions due to natural drivers those are missed by models

Solar signals in Sea Level Pressure and Sea Surface Temperature

We investigate solar cycle signals in 150 years of Sea Level Pressure (SLP) and Sea Surface Temperature (SST) data, using multiple regression analysis. We detect a solar signal in both SLP and SST in the North Pacific during DJF, similar to that found by Van Loon et al. (2007) but of smaller magnitude. We do not, however, identify the signal they found in the tropics. Our results do not support mechanisms for a solar influence on climate directly involving tropical SSTs. We have used different reconstructions of total solar irradiance to investigate the sensitivity of the results. The series of Krivova & Solanki and Foster give similar results to those acquired using sunspot number but the Hoyt & Schatten solar index sometimes produces different results because of mixing of the solar signal with a long-term trend. Using different approaches Labitzke and van Loon (1992) and Camp and Tung (2007), arrived at different results for a solar influence on winter stratospheric polar temperatures and its relationship to the quasi-biennial oscillation (QBO) in tropical stratospheric zonal winds. We show that these differences appear different largely because of their choices of QBO height. We also show that the effect of the QBO (30, 40 or 50 hPa) combined with solar activity reveals a clear signal in polar annular modes expressed in SLP. We show that the nature of ENSO was different before 1950s (and after1997): this may affect any solar influence. Other authors have suggested that tropical circulations were different during the intervening period. Such observation may have implications relating to the sun, tropical circulation and climate change. During 1958-1997, omission of ENSO from regression gives false warming (cooling) signal of higher (lower) solar on SST in tropics. Such analysis, accompanied by our observation that the years of peak annual sunspot number used by van Loon et al. (2007) generally falls a year or more in advance of the maximum of the smoothed DSO, provides coherence to some apparently conflicting findings. Finally, an atmosphere-ocean coupling process, (mainly involving the Pacific Ocean) is proposed to account for the solar influences. This coupling appears to be disturbed during the later half of the 20th century, probably due to climate change