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Modern ocean–atmosphere interactions in the northeastern Pacific Ocean have a significant effect on the climate of the west coast of North America. We present radiolarian microfossil-based temperature reconstructions for the eastern North Pacific spanning the past 20,000 yr to examine possible correlations and linkages between continental climate change and changes in sea surface temperature (SST) in the northeastern Pacific Ocean on millennial time scales. The reconstructions indicate that the regional pattern of ocean circulation off the west coast of North America was further south 15,000 cal yr B.P. than it is today, and reached its present location 13,000 cal yr B.P. The North Pacific Drift and Transition Zone were further south as a result of a more southerly North Pacific high pressure cell prior to 13,000 cal yr B.P. While two continental paleoclimate records from northwestern North America show regional differences, they also can be correlated to the SST changes. A coastal site at 48°N shows similar patterns in summer temperatures, as observed in offshore marine records of SSTs. However, an inland continental record seems to reflect more-regional-scale changes in sea surface conditions showing a thermal maximum centered at 10,000 cal yr B.P which is observed in the marine transect south of 42°N. We conclude, based on the pattern of oceanographic change as reflected in radiolarian assemblages, that changes in the past latitudinal position of the North Pacific Drift played a significant role in controlling continental climate immediately to its east, as it does in the present environment. We also conclude that during the past 20,000 yr much of the evolution of oceanographic change is related to the migration of the atmospheric pressure cells (the North Pacific high and Aleutian low) of the northeastern Pacific.

An account of the 1994 hurricane season in the eastern North Pacific Ocean is given. The numbers of hurricanes and tropical storms were near normal, but the activity tended to occur farther to the west in the basin than usual. Hurricane Rosa was the only system of the season to make landfall.

The 1994 Atlantic hurricane season had only three hurricanes forming from just seven tropical storms. Several of these tropical cyclones, however, caused loss of life and great damage. Gordon, as a tropical storm, produced floods that killed more than 1100 people in Haiti. Alberto, Beryl, and Gordon hit the United States, causing 38 deaths and nearly $1 billion in damage over the southeastern states.

Phase A of the NASA Pacific Exploratory Mission in the western North Pacific (PEM- West A) region was conducted during September-October 1991. The background meteorology of eastern Asia and the western North Pacific region during the PEM-West A study is described. Mean large-scale flow patterns are discussed along with transient synoptic scale features (e.g., midlatitude cyclones, anticyclones, and frontal systems) responsible for long-range transport of trace species over the study region. Synoptic summaries are given for each of the 18 data flights, together with selected examples of meteorological processes that gave rise to some of the changes observed in the measured trace gases. Examples of large-scale ozone features observed above and below the DC-8 flight altitude by an onboard lidar system are also related to meteorological processes such as stratospheric-tropospheric exchange and upward transport of air from the boundary layer. The broad objectives of the National Aeronautics and Space Administration's (NASA) Pacific Exploratory Mission in the west- ern North Pacific (PEM-West) region are to study the chemical processes and long-range transport of trace gas species over the Pacific Ocean and to estimate the human impact on chemistry of the troposphere in this region. Specifically, the major objectives of PEM-West are to understand the factors influencing the budgets of ozone and sulfur. The overall experimental design of PEM-West encompassed two intensive airborne field studies positioned in time such that contrasting meteorological regimes in the western North Pacific could be sampled. The firat phase, PEM-West A, was conducted during September-October 1991, a period in which the lower tropospheric airflow was dominated by flow from the mid- Pacific regions. The phase B was conducted in March 1994, a period characterized by maximum outflow from the Asian continent.

The effects of global climate change on hurricane activities have been the subject of constant debate in recent years. An analysis of the hurricane database (HURDAT) maintained by the National Hurricane Center reveals a change in the annual hurricane (or storm) genesis frequency in the Atlantic basin in recent years. Some studies have projected increases in both the frequency and intensity of landfalling hurricanes along the U.S. coastline in the near future. This paper presents the results of a preliminary study of the influences of possible change in the hurricane genesis frequency on the hurricane landfall rates and wind speed distributions along the U.S. coastline. A state-of-the-art stochastic hurricane simulation model was utilized to simulate and project the future hurricane activities. Instead of generating the number of storms per year based on a constant mean frequency, computed using historical data, two new hurricane genesis models were derived to project the future storm genesis frequency. The stochastic hurricane simulation model incorporating the new genesis models was utilized to generate multiple realizations of hurricane seasons for the next 50 years (2012 to 2161). The results of this preliminary study show appreciable increases in both the landfall rates and wind speeds under two different hurricane climate change scenarios. In particular, the results indicate that more storms are likely to strike the Florida peninsula and coastal regions of Georgia, South Carolina and North Carolina.

A total of 70 tropical waves (also known as African or easterly waves) were counted in the Atlantic basin during the 1993 hurricane season. These waves led to the formation of 9 of the 10 total number of tropical cyclones in the Atlantic hurricane basin. It appears that tropical waves led to the formation of practically all of the eastern Pacific tropical cyclones in 1993.

The 1993 hurricane season is summarized. and individual tropical storms and hurricanes are described. Overall, the season was relatively inactive, but tropical storms and hurricanes were responsible for a large number of deaths in South America, Central America, and Mexico. Only one hurricane, Emily, made landfall in the United States.

The National Hurricane Center tracked 14 tropical storms, 10 of which became hurricanes, during the 1993 eastern North Pacific hurricane season. Four named tropical cyclones and one tropical depression made landfall in Mexico. A general overview of the 1993 hurricane season is presented.

Hurricane Irene followed a track that curved northward over the Bahamas and ran directly over the U.S. east coast from Cape Hatteras to New England in August of 2011, causing severe storm surges, intense inland flooding, loss of life and over $8 billon in storm damage. While the ensemble of atmospheric forecast models accurately predicted the hurricane timing and track, the hurricane intensity was consistently over-predicted. Data from the U.S. Integrated Ocean Observing System (IOOS) were used to better understand the potential impact of the Mid-Atlantic Bight's coastal ocean on the Hurricane Irene intensity forecast.

The overarching objectives of this research project are to obtain an improved understanding of the formation, intensification, predictability and structure change of tropical cyclones in the Western Pacific region. These new insights will ultimately improve forecast guidance for U.S. Naval operations in this region. During this past year the PI and his research group have developed and further substantiated a new model for the phenomenon of secondary eyewall formation (SEF), a process that occurs frequently in mature tropical cyclones and is a continued forecast priority for storms threatening Naval and DOD operations in the Western North Pacific sector. The new model is based on a newly articulated paradigm of tropical cyclone intensification (discussed further below) that the PI has developed in collaboration with his distinguished international colleague, Professor Roger Smith from the University of Munich. Because of space constraints, only pertinent background information is provided to explain the basis for the new approach followed by a summary of some of the key new findings on the SEF problem. Other research supported by this grant is discussed in preceding annual reports and via the PI s website listed above.

The eastern tropical Pacific plays a key role in the tropical atmospheric circulation and in the global carbon cycle, and assessing the sensitivity of this region to global climate changes is a major challenge facing climatologists. Provided here is a synthesis of proxy records of the mean climate of the mid-Holocene (5-8 ka) along the south eastern Pacific margin and four regions of South America. These regions were selected for the strength and stability of ENSO teleconnections, and located outside the direct influence of the intertropical convergence zone or the southern westerlies in order to avoid the overprinting signal of their insolation-related variations and focus on the relationship between the eastern tropical Pacific and South America. This study is based on a review of published multiproxy data as well as new isotopic data from the Peruvian and Chilean coast. The available evidence indicates that sea-surface temperatures were similar to 1-4 degrees C cooler from the Galapagos to the southern Peruvian coast as a result of increased coastal upwelling forced by changes in longshore windfields. The mean La Nina-like conditions in the eastern South Pacific were associated to aridity in southern Brazil and along the whole South American Pacific coast from central Chile to the Galapagos, and to wetter conditions on the western central Andes. This regional synthesis provides a coherent picture of the South American mean climate that is very similar to the modern precipitation pattern observed during La Nina conditions, suggesting that atmospheric teleconnections linking the South Eastern Pacific to these continental areas were similar in the middle Holocene.

The recent increase of North Atlantic TC activity has attracted considerable attention especially since the exceptional hurricane season of 2005. Causes for this increase have been hotly debated in an attempt to determine whether it is within a range of natural variability, the result of global warming, or merely a byproduct of an inhomogeneous TC record.

Hurricane Andrew was a relatively small but intense hurricane that passed through the Bahamas, across the Florida Peninsula, and across the Gulf of Mexico between 23 and 26 August 1992. The characteristics of this hurricane primarily beyond its core are summarized using 1) marine observations from three National Data Buoy Center (NDBC) buoys and three Coastal-Marine Automated Network stations close to the storm track; 2) water levels and storm surge at 15 locations in the Bahamas, around the coast of Florida, and along the northern coast of the Gulf of Mexico; 3) currents, temperatures, and salinities at a depth of 11 m in the northern Gulf; and 4) spatial analyses of sea surface temperature (SST) before and after the passage of Andrew. Sea level pressure, wind direction, wind speed, wind gust, air temperature, and the surface wave field were strongly influenced at locations generally within 100 km of the hurricane track. Maximum sustained winds of 75 m s−1 occurred just north of the storm track ...

The National Hurricane Center tracked a record-breaking 27 tropical cyclones in the eastern North Pacific Ocean during 1992. Of the 27, 24 became tropical storms (also a record) and 14 became hurricanes. These records are based on data starting in 1966, which is when routine satellite surveillance began. Four hurricanes affected mainland Mexico.

Hydrographic measurements by CTD were made in the western-central Equatorial Pacific (160°W–147°E) during the Japanese Pacific Climate Study cruise in January–February 1991. InT-S diagram, three water masses are seen in the layer of σθ kg/m3: salinity water corresponding to the Tropical Water of eastern South Pacific origin, less saline water in the North Pacific, and water with salinity between the above two, found on the equator. In three meridional sections (160°W–160°E), the Tropical Water of eastern South Pacific origin extends further equatorward than the climatological data of Levitus (1982).

The 1992 hurricane season is summarized, including accounts of individual storms. Six tropical storms were tracked, of which four became hurricanes. In addition, one subtropical storm formed during the year. The season will be remembered most, however, for Hurricane Andrew. Although Andrew was the only hurricane to make landfall in the contiguous United States during 1992, it earned the distinction of becoming the most expensive natural disaster in United States history.

A total of 69 tropical waves (also known as African and easterly waves) were counted in the Atlantic basin during the 1992 hurricane season. As was the case in 1991, the waves were, in general, relatively weak. These waves led to the formation of only four tropical depressions in the Atlantic hurricane basin, of which one intensified into a tropical storm and another intensified into Hurricane Andrew. Andrew was the only 1992 Atlantic hurricane to originate from a tropical wave. There were five additional tropical depressions that were primarily initiated by systems of nontropical origin. These produced three hurricanes and one tropical storm. It appears that tropical waves led to the formation of practically all of the eastern Pacific tropical cyclones in 1992.

[1] The 2010 Atlantic hurricane season was extremely active, but no hurricanes made landfall in the United States, raising a question of what dictated the hurricane track. Here we use observations from 1970–2010 (also extending back to 1950) and numerical model experiments to show that the Atlantic warm pool (AWP) – a large body of warm water comprised of the Gulf of Mexico, the Caribbean Sea and the western tropical North Atlantic – plays an important role in the hurricane track. An eastward expansion of the AWP shifts the hurricane genesis location eastward, decreasing the possibility for a hurricane to make landfall. A large AWP also induces barotropic stationary wave patterns that weaken the North Atlantic subtropical high and produce the eastward steering flow anomalies along the eastern seaboard of the United States. Due to these two mechanisms, hurricanes are steered toward the northeast without making landfall in the United States. Although the La Nina event in the Pacific may be associated with the increased number of Atlantic hurricanes, its relationship with landfalling activity has been offset in 2010 by the effect of the extremely large AWP.

This article documents long-term characteristics of tropical cyclones (TCs) in the eastern Pacific Ocean from 1970 through 2009. This basin is relatively active during the summer and the presence of TCs may result in significant changes in atmospheric moisture and convective activity over populated areas along the west coast of Mexico. Because of its length and geographical location, the Baja California Peninsula received more than 30 landfalls during the period considered. To demonstrate their impact, four case studies from recent seasons were selected for further analysis. The analysis includes examination of TC position and intensity records, satellite imagery, meteorological gridded fields, and surface rainfall observations that are used to illustrate the evolution of these cyclones prior to and during landfall.

[1] This study examines the different impacts of two types of El Ninos, the eastern Pacific El Nino (EP-EN) and the central Pacific El Nino (CP-EN), on tropical cyclone (TC) tracks over the western North Pacific (WNP) based on observational data. Whereas TC tracks between CP-EN and EP-EN show a small difference in boreal summer (JJA), they do exhibit a great difference in boreal autumn (SON), that is, TCs recurve northward at a further westward location near the coastline of East Asia during CP-EN. As a consequence, more TCs make landfall to Taiwan and South China during CP-EN. A further observational analysis indicates that the westward shift of the subtropical high and associated steering flow during CP-EN is a key factor that causes the difference in the TC tracks in autumn. Numerical experiments further suggest that the difference of local SST in the WNP between CP-EN and EP-EN accounts for the distinctive differences in the local Hadley circulation, the subtropical high and the TC steering flow.

The 2009 eastern North Pacific hurricane season had near normal activity, with a total of 17 named storms, of which seven became hurricanes and four became major hurricanes. One hurricane and one tropical storm made landfall in Mexico, directly causing four deaths in that country along with moderate to severe property damage. Another cyclone that remained offshore caused an additional direct death in Mexico. On average, the National Hurricane Center track forecasts in the eastern North Pacific for 2009 were quite skillful.

A hurricane is a large rotating storm with a central area of very low pressure and strong winds greater than 74 mph (118 km/h).1 The hurricane is graded 1–5 in relation to the strength of the winds, which can be greater than 155 mph (249 km/h, category 5).2 Hurricanes arise from warm, moist air from tropical oceans, and with global warming, hurricanes are occurring more frequently and with greater severity.3 Tropical storms originating in the Atlantic Ocean or the Eastern North Pacific Ocean (ie, the Northern hemisphere) are termed hurricanes, whereas those that originate from the Pacific Ocean are known as typhoons and those from the Indian Ocean as cyclones.1 Hurricanes are a major problem for countries in the Caribbean and Central and Latin America. The word ‘hurricane’ is thought to be derived from either the Carib god ‘Hurican’ or the Mayan god ‘Hurakan,’ who caused a great storm and flood by blowing his breath across the ocean.4 It has been estimated that almost two million people worldwide have died from tropical storms (hurricanes, typhoons and cyclones) in the last two centuries.1 In the 20th century alone, there have been 75 000 deaths from hurricanes in North America and the Caribbean, including almost 10 000 deaths from hurricane Mitch, which affected Central America in 1998.5 The impact of hurricanes on health can be divided into immediate and during the recovery phase. Drowning during the hurricane used to account for the majority of the deaths. The use of warning systems combined with evacuation has, however, dramatically reduced drowning deaths.1 3 During hurricane Katrina, however, two-thirds of the fatalities were thought to be due to the direct physical effects of the flood, and the majority of the deaths were thought to be due to …

The 2008 Atlantic hurricane season is summarized and the year’s tropical cyclones are described. Sixteen named storms formed in 2008. Of these, eight became hurricanes with five of them strengthening into major hurricanes (category 3 or higher on the Saffir–Simpson hurricane scale). There was also one tropical depression that did not attain tropical storm strength. These totals are above the long-term means of 11 named storms, 6 hurricanes, and 2 major hurricanes. The 2008 Atlantic basin tropical cyclones produced significant impacts from the Greater Antilles to the Turks and Caicos Islands as well as along portions of the U.S. Gulf Coast. Hurricanes Gustav, Ike, and Paloma hit Cuba, as did Tropical Storm Fay. Haiti was hit by Gustav and adversely affected by heavy rains from Fay, Ike, and Hanna. Paloma struck the Cayman Islands as a major hurricane, while Omar was a major hurricane when it passed near the northern Leeward Islands. Six consecutive cyclones hit the United States, including Hurricanes Dolly, Gustav, and Ike. The death toll from the Atlantic tropical cyclones is approximately 750. A verification of National Hurricane Center official forecasts during 2008 is also presented. Official track forecasts set records for accuracy at all lead times from 12 to 120 h, and forecast skill was also at record levels for all lead times. Official intensity forecast errors in 2008 were below the previous 5-yr mean errors and set records at 72–120 h.

In recent weeks, a number of Central South Pacific nations and territories have suffered a battering from an onslaught of intense cyclones occurring in quick succession. In early February, tropical cyclone (TC) Oli thrashed remote Tubuai in French Polynesia, tearing down buildings and pulverizing

The hurricane season of 2008 in the eastern North Pacific basin is summarized, and the individual tropical cyclones are described. Official track and intensity forecasts of these cyclones are also evaluated. The 2008 eastern North Pacific season was relatively quiet, with overall activity at about 75% of the long-term median. A total of 16 tropical storms formed, of which 7 became hurricanes and 2 became major hurricanes. One hurricane, one tropical storm, and two tropical depressions made landfall in Mexico, causing eight direct deaths in that country along with significant property damage. In addition, Tropical Storm Alma was the first tropical cyclone on record to make landfall along the Pacific coast of Nicaragua. On average, the official track forecasts in the eastern Pacific for 2008 were quite skillful and set records for accuracy from 1 to 3 days. However, no appreciable improvement in mean intensity forecast skill was noted.

Major hurricanes are prominent meteorological hazards of the U.S. Atlantic and Gulf coasts. However, the official modern record of Atlantic basin tropical cyclones starts at 1851, and it does not provide a comprehensive measure of the frequency and magnitude of major hurricanes. Vast amounts of documentary weather data extend back several centuries, but many of these have not yet been fully utilized for hurricane reconstruction. These sources include weather diaries, ship logbooks, ship protests, and newspapers from American, British, and Spanish archives. A coordinated effort, utilizing these historical sources, has reconstructed a major hurricane in August 1812, which is the closest to ever pass by New Orleans, Louisiana, including Hurricane Katrina. The storm became a tropical depression in the Caribbean Sea, passed south of Jamaica as a tropical storm, and then strengthened to hurricane strength in the Gulf of Mexico. It made landfall about 65 km southeast of New Orleans and passed just to the west of the city. Historical storm surge and damage reports indicate it as a major hurricane at landfall. Given that conditions during 1812 include having lower sea level, higher land elevation prior to human-induced subsidence, and more extensive wetlands, a recurrence of such a major hurricane would likely have a greater detrimental societal impact than that of Hurricane Katrina. The 1812 hurricane study provides an example of how historical data can be utilized to reconstruct past hurricanes in a manner that renders them directly comparable with those within our modern record.

The analyses based on the observational data show that the tropical cyclone (TC) numbers tend to become decreasing over some oceanic basins during the recent multiple decades despite a rise in their sea surface temperatures (SSTs). A methodology of understanding the mechanism responsible for such seemingly counter intuitive phenomena is suggested in this chapter and thus the causality between the unusually heterogeneous pattern of SSTs in warming environment and TC frequency over, as an example, the western North Pacific (WNP) is explained. This methodology is important in that it provides an insight into the problem why under global warming high SSTs as one of the necessary conditions for TC genesis should unexpectedly contribute to TC number reduction, though locally, and furthermore, in view of that such phenomena have also been observed over the other oceanic basins than the WNP and that the principle of the technique is universal, this procedure of analysis can be expected to apply globally to examine the extreme weather/climate extent frequency trend in the worldwide warning conditions.

The 1991 hurricane season is summarized, including accounts of individual storms. Eight tropical storms were tracked, of which four became hurricanes. Only one tropical cyclone, Hurricane Bob, hit the United States.

The 1991 eastern North Pacific hurricane season is summarized. The season comprised 16 tropical cyclones, consisting of 10 hurricanes, 4 tropical storms, and 2 tropical depressions.

This paper provides a summary of some of the recent studies of the climate of tropical cyclone (TC) activity in the Western North Pacific (WNP) region, and its possible relation with global warming. Because two recent review articles (Chan 2004, 2005) have summarized most of the research on this topic up to around 2002, this paper will only discuss the studies that came after this time. Readers interested in the earlier works can consult these two articles. Section 2 discusses the variations of TC numbers and number of intense TCs and how they might or might not be related to global warming. Variations of TC tracks and landfall locations are presented in Section 3. A summary is then given in Section 4.

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The 1990 eastern Pacific hurricane season is summarized. Twenty tropical storms were tracked of which 16 became hurricanes. Hurricanes Hernan and Trudy were among the strongest ever observed in this area. Rachel was the only system to make landfall.

The 1991 hurricane season produced 76 tropical waves of which 12 became tropical depressions. African seedlings initiated 10 of the 14 named Atlantic storms and all of the eastern Pacific tropical cyclones. A comparison with previous years is presented.

The 1990 hurricane season is summarized, including accounts of individual storms. Fourteen tropical stormswere tracked of which eight became hurricanes. Only one storm, Marco, hit the United States.

lems facing the small fisheriesdependent States of the South Pacific. The establishment of 200-mile exclusive economic zones (EEZs) is described and the implications of the EEZs for regional and distant water fishing States are analysed. The article then examines the founding of the South Pacific Forum and its relationship to Article 64 of the Law of the Sea Convention. A number of recent issues between the South Pacific forum and distant water fishing States are described, including the Danica and Jeaneffe Diana cases and drift net fishing by Japanese and Taiwanese boats.

[1] In the 2008 North Atlantic hurricane season, July was anomalously active with four tropical storms, of which two intensified to become hurricanes. The 2007 season experienced an uncommon May storm and an equally uncommon December storm. The 2005 season was the most active in the secular record, and was also anomalously active during the typically quiescent early and late portions of the season. This recent increase in early- and late-season activity has raised questions about the effect that climate change may be having on the length of the hurricane season. Here I report on the observed trends in the annual distribution of North Atlantic tropical storm formation events and their relationship with tropical Atlantic sea surface temperatures (SST). I find an apparent tendency toward more common early- and late-season storms that correlates with warming SST, but the uncertainty in these relationships is high.

The coastal region comprising the states of Louisiana, Mississippi, and Texas is frequently impacted by meteorological events such as frontal passages and hurricanes. The region is also influenced by the Mississippi river, which is seventh largest in terms of water and sediment discharge among the major rivers of the world that strongly influences the physical and biogeochemical properties in the northern Gulf of Mexico. NASA remote sensing data such as winds from QuikSCAT, sea surface height anomaly (SSHA) from Jason-1, ocean color and sea surface temperature (SST) from MODIS satellite sensors were assessed during the period that Hurricane Rita made landfall on 24 September 2005 along the Louisiana-Texas border in the western Gulf of Mexico. QuikSCAT winds revealed the northwestward movement of the hurricane and gradients in the distribution of wind speed around the hurricane center. Altimeter data indicated changes in pattern of the SSH anomaly field and a displacement of the warm and cold core eddies following the hurricane. Although limited by cloud cover, the MODIS 8-day average chlorophyll imagery obtained before and after the hurricane indicated an offshore displacement of higher chlorophyll concentrations while the MODIS 250 m resolution true color imagery showed high levels of suspended particulate matter in the impacted coastal region. MODIS SST indicated a cooling of the surface waters around and east of the track following Hurricane Rita. The use of multiple remote sensing products provided better insights of the oceanographic response to Hurricane Rita.

[1] Plentiful documentary and pre-twentieth century instrumental data from Louisiana, U.S.A., provide a record of continuous tropical cyclones, with daily resolution dating back to the late eighteenth century. The reconstruction provided new specific information for 83 storms prior to 1872. Parts of the early and mid-nineteenth century exhibit greater tropical cyclone and hurricane activity than at any time within the last few hundred years. A major hurricane that impacted southeast Louisiana in August 1812 is very likely the closest landfalling hurricane known to impact New Orleans. The longer temporal perspective provides insight on historical hurricane impacts and information on assessing future hurricane mitigation strategies concerning potential worst-case scenarios.