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The article presents comments and criticisms on the published paper "Hurricanes and global warming. This is presentation of the views and scientific perspectives as well as the perspectives on structure and function of scientific assessments given by Anthes et al.(2006) and Pielke et al. (2005). The policy action in question here deals with what could be the most effective policy with regards to tropical cyclone that have an impact in the societal vulnerability. There is an on-going investigation on the issues of research in climate changes and tropical cyclones. Also, a brief enumeration on the criticisms by Pielke et al.(2005) and Anthes et al.(2006) is emphasized.

This article discusses climate change and hurricanes. Papers that appeared in the scholarly journals "Nature" and "Science" during the summer of 2005 raised the question of global warming being the cause of the record-breaking hurricane season of 2005. The article examines that argument, noting that many scientists believe that human-induced climate warming is indeed real. Also discussed is the increasing intensity of hurricanes since 1975, as well as the rise in seas surface temperatures and greenhouse gases in the atmosphere.

The study investigates the local climatological minimum of tropical cyclogenesis over the eastern Caribbean Sea. This area, colloquially known by forecasters as the "hurricane graveyard," is located within the deep tropical easterlies. Tropical disturbances emerging from the African continent usually pass through the Lesser Antilles and into the eastern Caribbean. Satellite imagery shows disturbances that frequently exhibit decreasing convection in an area bounded by the islands to the north and east, Venezuela to the south, and roughly 75°W longitude to the west. Quick Scatterometer (QuikSCAT)-derived surface winds during clear-sky conditions frequently show the presence of accelerating easterlies in the central Caribbean as part of the Caribbean low-level jet (CLLJ). Analysis of the National Centers for Environmental Prediction- National Center for Atmospheric Research (NCEP-NCAR) reanalysis project wind fields suggests the presence of an area of persistent low-level mass divergence over the eastern Caribbean. This implies a subsident regime that would weaken convection. Climatologically, this phenomenon reaches peak intensity in July, and then shifts toward the east and weakens during the latter half of the Atlantic hurricane season. This is reflected by the local minimum of tropical cyclogenesis points in the National Hurricane Center's best-track data in the early part of the season. The intensity of the low-level divergence in the eastern Caribbean is shown to be correlated with the Southern Oscillation index. The divergent low-level easterly flow can also enhance the vertical wind shear and help lower sea surface temperatures, further inhibiting tropical cyclogenesis. The local minimum of tropical cyclogenesis in this region has important implications to operational forecasting, because the vast majority of tropical cyclones in the Caribbean eventually affect surrounding landmasses. [ABSTRACT FROM AUTHOR]

The State of the Climate 2005 report summarizes global and regional climate conditions and places them, where possible, into the context of historical records. Descriptions and analyses of notable climatic anomalies, both global and regional, also are presented. According to the Smith and Reynolds global land and ocean surface temperature dataset in use at the NOAA National Climatic Data Center (NCDC), the globally averaged annual mean surface temperature in 2005 was the warmest since the inception of consistent temperature observations in 1880. Unlike the previous record positive anomaly of 1998 (+0.50°C), the 2005 global anomaly of 0.53°C above the 1961–90 mean occurred in the absence of a strong El Niño signal. The record ranking of 2005 was corroborated by a dataset maintained at NASA, while United Kingdom archives placed 2005 second behind 1998. However, statistically, the 2005 global temperature anomaly could not be differentiated from either 1998 or any of the past four years. The majority of the top 10 warmest years on record have occurred in the past decade, and 2005 continues a marked upward trend in globally averaged temperature since the mid-1970s. Lower-tropospheric temperature was the second warmest on record, with northern polar regions the warmest at 1.3°C above the 1979–98 mean. Unlike air temperatures, globally averaged precipitation was near normal relative to the 1961–90 period mean value. The global 2005 anomaly was just -0.87 mm. Over the past 25 years, only 7 years have had above-normal precipitation. Additionally, in 2005, only September–November experienced a positive anomaly. Northern Hemisphere snow cover extent was 0.9 million km2 below the 36-year average (fifth lowest) and Arctic sea ice extent was record lowest in all months of 2005 except May, resulting in a record lowest annual average Arctic sea ice extent for the year and continuing a roughly 8% yr-1 decline in ice extent. Carbon dioxide (CO2) concentrations rose to a global average of 378.9 parts per million (ppm); about 2 ppm over the value from 2004. This record CO2 concentration in 2005 continues a trend toward increased atmospheric CO2 since the preindustrial era values of around 280 ppm. The globally averaged methane (CH4) concentration in 2005 was 1774.8 parts per billion (ppb), or 2.8 ppb less than in 2004. Stratospheric ozone over Antarctica reached a minimum of 110 Dobson units (DU) on 29 September. This represented the 10th lowest minimum level in the 20 years of measurement of stratospheric ozone. In the global ocean, sea level was above the 1993–2001 base period mean and rose at a rate of 2.9 ±0.4 mm yr-1. The largest positive anomalies were in the Tropics and Southern Hemisphere. Globally averaged sea surface temperature (SST) also was above normal in 2005 (relative to the 1971–2002 mean), reflecting the general warming trend in SST observed since 1971. In the Tropics, only a weak warm phase of El Niño materialized, but dissipated by March. A relatively active Madden–Julian oscillation (MJO) resulted in the disruption of normal convective patterns in the tropical Pacific and generated several Kelvin waves in the oceanic mixed layer. In the Atlantic Ocean basin, there was record tropical storm activity, with 27* named storms (15 hurricanes). Three became category 5 storms on the Saffir–Simpson scale, and Hurricane Wilma set a new record for the lowest pressure (882 hPa) recorded in the basin. Both Hurricanes Stan and Katrina had exceptional death tolls, and Katrina became the costliest storm on record. Below-normal tropical storm activity in several other basins resulted in near-normal conditions globally in 2005. Regionally, annual and monthly averaged temperatures were above normal across most of the world. Australia experienced its warmest year on record, as well is its hottest April. For both Russia and Mexico 2005 was the second warmest year on record. Intermittent and delayed monsoons in Africa and East Asia resulted in below-normal precipitation in many areas. Drought continued in much of the Greater Horn of Africa and developed in the central United States. Record severe drought occurred over both the Iberian Peninsula and western Amazonia in 2005. In the Amazon, river levels dropped by as much as 11 m between May and September. Conversely, heavy snows early in 2005 combined with a warm boreal spring to generate widespread flooding in areas of southwest Asia. Canada experienced its wettest year on record in 2005, with flooding in Alberta, Manitoba, and Ontario. In July, the South Asian monsoon delivered a record 944.2 mm of precipitation over 24 h to areas around Mumbai, India. [ABSTRACT FROM AUTHOR]