Recent Publications | Carolina Tree-Ring Science Laboratory

Recent Publications

Carolina Tree-Ring Science Laboratory affiliation in bold and current/former student affiliation italicized 


Mitchell, T.J. and Knapp, P.A. 2024. A comparison of intense and total summer-rainfall amounts in central North Carolina, USA using tree-ring data from 1770–2020. Water 16, 513.

Soulé, P. T., & Knapp, P. A. . The evolution of “Hot” droughts in Southern California, USA from the 20th to the 21st century. Journal of Arid Environments. 220, 105118,

Knapp, P. A., Soulé, P. T., Mitchell, T. J., Catherwood, A.A., Lewis, H.S.. Increasing radial growth in old-growth high-elevation conifers in Southern California, USA, during the exceptional “hot drought” of 2000–2020. International Journal of Biometeorology.


Catherwood A.A., Mitchell T.J., and Knapp P.A. A dendroecological method to examine summertime soil-moisture changes: a case study from North Carolina, USA. Trees 37, 599–607 (2023).

Carlton G.J., Knapp P.A. and Mitchell T.J., Global Patterns of Antioxidant-Rich Food Crops Based on Geographical Origins. The Professional Geographer, pp.1-11. DOI: 10.1080/00330124.2023.2207632

Lewis H.S. and Knapp P.A. 21st Century Warming, Site Aspect, and Reversal of Age-Related Growth Decline in Shortleaf Pine (Pinus echinata) in North Carolina, USA. Atmosphere14, 1240.

Catherwood A.A. and Knapp, P.A. Increasing precipitation variability and climate-growth responses of five tree species in North Carolina, USA. Environmental Research: Climate. 3(1) DOI: 10.1088/2752-5295/ad0445



Catherwood A.A., Knapp P.A., and Mitchell T.J. Scientific Note: Loblolly Pine Traumatic Resin Ducts Serve as Indicators of Cool-Season Weather Events at Nags Head, North Carolina. Castanea 86(2), 296-304,

Mitchell T.J., Knapp P.A., Ortegren J.T.. Observations on the Frequency, Duration, and Geographical Extent of Summertime Cold-Front Activity in the Southeastern USA: 1973–2020. Meteorology. 1(2):211-219.

Mitchell T.J., Knapp P.A.. Radial Growth Responses of Four Southeastern USA Pine Species to Summertime Precipitation Event Types and Intense Rainfall Events. Atmosphere. 13(10):1731.

Rother, M.T., Patterson, T.W., Knapp, P.A., Mitchell T.J., Allen N A tree-ring record of historical fire activity in a piedmont longleaf pine (Pinus palustris Mill.) woodland in North Carolina, USA. fire ecol 18, 34.


Maxwell, J.T. Bregy, J.C., Robeson, S.M., Knapp, P.A., and Soulé, P.T. Recent increases in tropical cyclone precipitation extremes over the US East Coast. PNAS

Soulé, P.T., Knapp, P.A., Maxwell, J.T. and Mitchell, T.J. A comparison of the climate response of longleaf pine (Pinus palustris Mill.) trees among standardized measures of earlywood, latewood, adjusted latewood, and totalwood radial growth. TreesStructure and Function, 35: 10651074.

Knapp, P.A., Soulé, P.T., Maxwell, J.T., Ortegren, J.T. and Mitchell, T.J. Tropical cyclone precipitation regimes since 1750 and the Great Suppression of 18431876 along coastal North Carolina, USA. International Journal of Climatology, 41: 200210.


Mitchell, T.J., Knapp, P.A., and Patterson, T.W. The importance of infrequent, highintensity rainfall events for longleaf pine (Pinus palustris Mill.) radial growth and implications for dendroclimatic research. Trees, Forests and People.

Kaiser, A., Soulé, P.T., van de Gevel, S., Knapp, P.A., Bhuta, A. Walters, J. and Montpellier, E.E. Dendroecological investigation of redcockaded woodpecker cavity tree selection in endangered longleaf pine forests. Forest Ecology and Management, 473.

Montpellier, E., Knapp, P. A., Soulé, P., and Maxwell, J.T. Microelevational differences affected longleaf pine (Pinus palustris Mill.) sensitivity to tropical cyclone precipitation: A case study using LiDAR. TreeRing Research, 76: 8993.

Montpellier, E., Soulé, P., Knapp, P. A., and Perry, L.B. Reconstructing summer upperlevel flow in the northern Rocky Mountains using an alpine larch treering chronology. Climate Research, 79(3), 207218.

Bregy, J.C., Maxwell, J.T., Robeson, S.M., Ortegren, J.T., Soulé, P.T., and Knapp, P.A. Spatiotemporal variability of tropical cyclone precipitation using a highresolution, gridded (0.25° x 0.25°) dataset for the eastern United States, 19482015. Journal of Climate, 33: 18031819.


Soulé, P.T. and Knapp, P.A. Radial Growth Rate Responses of Western Juniper (Juniperus occidentalis Hook.) to atmospheric and climatic changes: A longitudinal study from central Oregon, USA. Forests, 10(12), 1127.

Montpellier, E.E., Soulé, P.T., Knapp,P.A., and Maxwell, J.T. Dendroclimatic assessment of ponderosa pine radial growth along elevational transects in western Montana, USA. Forests, 10(12), 1094.

Mitchell, T.J., Knapp, P.A.,and Patterson, T.W. Changes in southeastern USA summer precipitation event types using instrumental (19402018) and treering (17902018)data. Environmental Research Communications.

Mitchell, T.J., Knapp, P.A., and Ortegren, J.T. Tropical cyclone frequency inferred from intra-annual density fluctuations in longleaf pine in Florida, USA. Climate Research. doi:10.3354/cr01573.

Soulé, P. T., and Knapp, P. A. A 400-year reconstruction of wintertime Arctic sea-ice extent using a high-elevation, mid-latitude tree-ring record. International Journal of Biometeorology, 63, 1217.

Mitchell, T.J., Patterson, T.W., and Knapp, P.A. Comparison of climate–growth responses of montane and piedmont longleaf pine (Pinus palustris Mill.) chronologies in North Carolina. Trees, 33(2), 615-620.

Soulé, P.T., Maxwell, J.T., and Knapp, P.A. Climate-growth responses from Pinus ponderosa trees using multiple measures of annual radial growth. Tree-Ring Research, 75(1), 25-33.


Patterson, T.W., and Knapp, P.A. Longleaf pine masting, northern bobwhite quail, and tick-borne diseases in the southeastern United States. Applied Geography, 98, 1-8.

Patterson, T.W., and Knapp, P.A. Longleaf pine cone–radial growth relationships in the southeastern USA. Dendrochronologia, 50, 134-141.

Watkins, K.E., Patterson, T.W., and Knapp, P.A. Investigating the Climatic Sensitivity of Shortleaf Pine on a Southeastern US College Campus. Southeastern Geographer, 58(2), 146-163.

Montpellier, E.E., Soule’ P.T., Knapp, P.A. and Shelly, J.S. Divergent growth rates of alpine larch trees in response to microenvironmental variability. Arctic, Antarctic, and Alpine Research 50 (1), e1415626 (9 pages),


Maxwell, J.T., Knapp, P.A., Ortegren, J.T., Ficklin, D. and Soule’ P.T. Changes in the mechanisms causing rapid drought cessation in the southeastern United States of America. Geophysical Research Letters DOI : 10.1002/2017GL076261.

Knapp, P.A. and Soule’, P.T. Spatio-Temporal linkages between declining Arctic sea-ice extent and increasing wildfire activity in the western United States. Forests 8(9), 313; doi:10.3390/f8090313.


Patterson, T.W. and Knapp, P.A. Scientific Note: Stand dynamics influence masting/radial growth relationships in Pinus palustris Mill.  Castanea  81(4) 314–322.

Hadley, K.S. and Knapp, P.A. Post-windstorm radial growth of Picea sitchensis and Pseudotsuga menziesii. MadroñoA West American Journal of Botany 63:234–248.

Knapp, P.A., Maxwell, J.T. and Soulé, P.T. Tropical cyclone rainfall variability in coastal North Carolina derived from longleaf pine (Pinus palustris Mill.): AD 1771–2014. Climatic Change 135:311–323.

Knapp, P.A., Maxwell, J.T., Ortegren, J.O. and Soulé, P.T. Spatio-temporal changes in comfortable weather duration in the continental U.S. and implications for human wellness. Annals of the Association of American Geographers 106:1–18

Patterson, T.W. and Knapp, P.A. Observations on a Rare Old-Growth Montane Longleaf Pine Forest in Central North Carolina. Natural Areas Journal. 36(2) 153–161.

Patterson, T.W., Cummings, L.W., and Knapp, P.A. Longleaf pine (Pinus palustris Mill.) morphology and climate/growth responses along a physiographic gradient in North Carolina. The Professional Geographer. 68(2) 238–248.


 Soulé, P.T. and Knapp, P.A. Sesquicentennial trends in intrinsic water-use efficiency: Analyses of intrinsic water-use efficiency indicate performance differences of ponderosa pine and Douglas-fir in response to CO2 enrichment. Journal of Biogeography 42: 144–155.


Patterson, T.W. Geographic Pattern Analysis of North Carolina Climate Division Data 1895–2013. Southeastern Geographer 54-3: 308–322.


Maxwell, J.T., Knapp, P.A. and Ortegren, J.T. Influence of the Atlantic multidecadal oscillation on tupelo honey production from AD 1800-2010. Agricultural and Forest Meteorology 174–175:129–134.

Knapp, P.A., Soulé, P.T. and Maxwell, J.T. Mountain pine beetle selectivity in old-growth ponderosa pine forests, Montana, USA. Ecology and Evolution, doi: 10.1002/ece3.522.

Soulé, P.T. and Knapp P.A. Radial growth rates of two co-occurring coniferous trees in the Northern Rockies during the past century. Journal of Arid Environments 94:87-95.


Knapp, P.A. and Hadley, K.S. A 300-Year History of Pacific Northwest Windstorms Inferred from Tree Rings. Global and Planetary Change 92-93: 257-266.

Maxwell, J.T., and Knapp, P.A. Reconstructed tupelo-honey yield in northwest Florida inferred from Nyssa Ogeche tree-ring data: 1850–2009. Agriculture, Ecosystems, and Environment 149: 100–108.