Additional possible evidence of uplift within the last 1,900 years also 

 is suggested by C^^ dates on a peat and underlying shell bed cropping out on 

 the seaward side of Hog Island on Virginia's eastern shore: The peat bed, 

 assumed to have formed at about high tide, and the shell bed, deposited below 

 low tide, now crop out some 5 ft above mean low water, and date from 1170 to 

 1900 years B.P., respectively. 



Rates of uplift suggested by three localities of dated horizons indicate 

 an average value of about 1.05 ft per century for the past 15,000 years, 

 although the rate of uplift varied with time and actually involves a calcula- 

 tion for subsidence between 6,000 and 2,000 B.P. The rate of uplift seems to 

 have approximated the rate of eustatic sea-level rise (about 2.8 ft per cen- 

 tury), between 15,000 and 8,000 B.P. Apparent reversal of crustal uplift 

 between about 6,000 and 2,000 B.P., coupled with continued eustatic rise of 

 sea-level, allowed for extensive flooding of the Susquehanna valley lowland 

 and eastern shore of Virginia. 



Crustal uplift appears to have resumed between 2,000 B.P. and the pres- 

 ent. The crustal-movement curve for the period 14,000-3,000 B.P. is remark- 

 ably similar to that found by Kaye and Barghoorn (1964) for the Boston area. 

 (Authors) . 



143 HAYDEN, B. P. 1984. "A Systematic Error in the Northern Hemisphere 

 Sea-Level Pressure Data Set," Monthly Weather Review . Vol 112, No. 11, 

 pp 2354-2357. 



The Northern Hemisphere daily sea- level pressures at 5° latitude/- 

 longitude grid intersections for the years 1899-1980 are extensively used by 

 researchers. Changes in the basis of this grid-point data record are given in 

 Trenberth and Paolino (1980). They also document 3263 "serious" errors. For 

 the most part these errors were over Asia in the years before 1922 and during 

 World War II. Recently a search was done of the daily pressure data tape and 

 recorded frequency of centers of low pressure for the Northern Hemisphere. 

 This process uncovered a complex but hemispherically systematic error in this 

 data that may pose problems when using certain types of analyses. The details 

 of this bias, its source and when it is likely to be encountered are presented 

 here as an addendum to Trenberth and Paolino 's benchmark work. 

 (Introduction) . 



144 HICKS, S. D. 1972a. "On the Classification and Trends of Long Period 

 Sea-Level Series," Shore and Beach . Vol 83, No. C3, pp 1377-1379. 



The dramatics of surf and longshore currents in the beach erosion pro- 

 cess overshadows the small but relentless changes in sea- level over years and 

 decades. Yet, these same variations in sea-level are the very agents that 

 prevent beach erosion-building equilibria. As such, it behooves those 

 interested in shore and beach preservation to attempt to understand yearly 

 variability and long period trends in sea- level and, hopefully, to predict 

 future levels. 



The present status of long period sea- level studies is: descriptions 

 for many areas including the United States, qualitative understanding of 



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