# Presentation: 268037

## Trends in Climate in Northern New York and Western Vermont

**Kathie Dello**
- March 28, 2008
- New England Association of Environmental Biologists
- Bartlett, NH

**Notes:**
test 

## global climate change in the 20th century

- Average air temperature has risen 0.6 oC over the past century
- Very likely caused by anthropogenic activity
- Greenhouse gas emissions
- Most abundant greenhouse gas is carbon dioxide (CO2)
- Current atmospheric CO2 concentration ~380 ppm
- Pre-industrial (1750) concentration ~280 ppm
- IPCC. (2007). In Solomon S., et al (Eds.), *Climate change 2007: The physical science basis. contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change*. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press.

## climate change in the northeastern US

- Collectively, the NE states are the world’s seventh largest source of CO2 emissions
- Observed warming of 1.1 oC in the 20th century
- Almost twice that of the observed global increase
- Since 1970, temperatures have risen 0.27 oC per decade
- Winter temperatures have risen 0.72 oC  per decade
- Precipitation has increased 5-10% over 20th century
- Multi-year drought in 1960s
- Frumhoff, P. C., McCarthy, J. J., Melillo, J. M., Moser, S. C., & Wuebbles, D. J. (2006). *Climate change in the U.S. northeast: A report of the northeast climate impacts assessment*. Cambridge, MA: Union of Concerned Scientists.
- Frumhoff, P. C., McCarthy, J. J., Melillo, J. M., Moser, S. C., & Wuebbles, D. J. (2007). *Confronting climate change in the US northeast: Science, impacts, and solutions. synthesis report of the northeast climate impacts assessment (NECIA)*. Cambridge, MA: Union of Concerned Scientists (UCS).
- Hayhoe, K., Wake, C. P., Huntington, T. G., Luo, L., Schwartz, M. D., Sheffield, J., et al. (2007). Past and future changes in climate and hydrological indicators in the US northeast.* Climate Dynamics, 28*(4), 381-407.

## Why study regional climate change?

- Localities need regionally accurate information for planning, mitigation and adaptation
- Northeast climate is highly variable
- Global models operate at a resolution too large for regional studies
- Does not account for intricate changes in land use, topography and elevation

## Wake et al. 2005

## are there discernible trends in climate in the Adirondack region?

- Evaluate trends in temperature and precipitation
- By station, climate division, and entire region
- annually, seasonally, monthly
- Evaluate trends in “extreme” or 24-hour maximum precipitation
- Daily

## data sources

- United States Historical Climatology Network (USHCN)
- Temperature and precipitation data
- USHCN is a subset of USCDD sites
- Recent climate studies advocate use of USHCN , as USCDD is prone to false trends in temperature and precipitation
- Corrected for:
- Measurement technique
- Min/Max temperature bias
- Urban heat island effect
- Station relocation

## site selection criteria 

- Period of record from 1950 - 2005
- Within 50km of Adirondack Park
- Site was eliminated if more than 3 consecutive months within a year were missing
- For daily analyses, record had to be 98% complete
- 22 sites analyzed for temp, 14 for precip,  9 for extreme precip

## study area

- Predominately rural in nature
- 3 cities with a population of over 50,000
- Albany, NY; Utica, NY; Burlington, VT
- All or portions of 17 counties in New York, 5 counties in Vermont
- 7 US Climate Divisions
- Encompass 46 “High Peaks”, at or above an elevation of 1,219 m
- Highest pt in NYS - Mount Marcy: 1,629 m

## regional climate

- Average temperature 1950-2005 (based on USHCN data)
- All sites: 6.33 oC
- Range: 4.85 oC (Northern Plateau) – 8.18 oC (Hudson Valley)
- Average precipitation
- Higher spatial variability than temperature
- Ranges from ~760 mm (Lake Champlain area) – 1260 mm (Western Adirondacks)

- New York State Climate Office, http://nysc.eas.cornell.edu

## results

- Temperature
- Annual (by station, regionally)
- Seasonal
- Precipitation
- Annual (by station)
- Seasonal (by station)
- 24-hour max precipitation
- 90th percentile and precipitation exceedance
- Independence River
- Analyses:
- Mann-Kendall test for trend (non-parametric), Sen’s slope
- Change per 50 and 30 years

## minimum temperature

**Notes:**
min

## minimum temperature

**Notes:**
min

## anomalies - minimum temperature

## average temperature

- average temperature

## average temperature

## anomalies - average temperature

## maximum temperature

## maximum temperature

## anomalies - maximum temperature

## temperature:

- 1970-2005

- clockwise, top to bottom
- -minimum temperature
- -average temperature
- -maximum temperature

## 0.54 oC/50 years 

**Clockwise, from top left: www.Cabinsatmillcreek.com, **_[www.adkcamp.com](http://www.adkcamp.com/)_**, **_[www.fortwilliamhenry.com](http://www.fortwilliamhenry.com/)_**,www.adirondackinns.com **

- 0.54 oC/50 years

- 0.94 oC/50 years*

- 0.42 oC/50 years

- 0.08 oC/50 years

- * Statistically significant @ 0.10 level

- changes in average temperature in the region

- 0.42 oC/50 years

## Slide 24

## anomalies – precipitation

## Slide 26

## October: precip. vs. max temp.

- Spearman’s rho calculated for stations with statistically significant increase in October precipitation
- Indian Lake  (p<.01, -.356)
- Lake Placid  (p<.05, -.331)
- Ogdensburg (p<.01, -.399)
- Dannemora  (p<.01, -.388)

## 24-hour precipitation events

- 9 sites analyzed
- 6: increasing, 4 significantly
- From 2.75 days/50 years (Lawrenceville) to 9.2 days/50 years in (Dannemora)
- 3: no change
- 3 largest increases on eastern side of basin, largest increase at highest latitude

## Site with largest trend in precipitation per 50 years

-  Highest values in 1998-2005, second 1990 - 1997

## Days with precipitation over the 90th percentile value (~18mm) 

- Days with precipitation over the 90th percentile value (~18mm)
- rose by 9.2 days/ 50 years (p<.01)

## Independence River 

- Independence River

- Winter-Spring Center of Volume

- Method adapted from: Hodgkins et al. 2003. Changes in the timing of high river flows in New England in the 20th century

## conclusions

- Overall there are increases in temperature and precipitation
- Especially from 1970-2005
- Largest increases occurred in annual minimum temperature
- Summer, not winter, warmed most
- Contrary to Northeast
- August
- Temperatures decreased in Fall
- October
- Regional average barely increasing, not SS

##  conclusions

- Site with largest increase in precipitation also had largest increase in 24-hour maximum precipitation
- Dannemora
- Seems to be a relationship between maximum temperature and precipitation
- Number of 1-day large precip events increasing

## What does this mean?

- Longer, hotter summers
- Could be a mixed blessing for the summertime recreation industry
- More recreation, more introduction of invasive species?
- Affect ecosystem
- Sugar maple, maple sugar production
- Longer warm growing season, but many “cool weather” crops in NE
- Dairy cattle perform best at 4 °C to 24 °C
- Shorter, warmer winters
- Earlier spring snowmelt
- Less snow, more dense snowpack
- Bad for ski industry ($)
- Ice fishing
- More lake effect events occuring as rain?

- United States Global Change Research Program. Climate Change Impacts on the US:Northeast. Accessed November 12, 2007 at http://www.usgcrp.gov/usgcrp/nacc/education/northeast/ne-edu-3.htm

- Wake, C., & Clean Air-Cool Planet. *Indicators of climate change in the northeast 2005*

- Kunkel, K.E., Westcott, N.E., Kristovick, D.A.R. (2002) Assessment of potential effects of climate change on heavy lake-effect snowstorms near lake erie. *Journal of Great Lakes Research*, 28(4), 521-536

## What does this mean?

- Wetter summer/fall
- But, observed droughts (2001)
- Leaves covering sewers in the more urbanized areas can produce flooding
- Uneven distribution of precipitation may cause flooding or droughts
- Requires significant resources for watershed management and planning

## What does this mean?

- Lake Champlain not freezing over
- Higher temp, lower dissolved oxygen
- Other chemical and biological affects
- Algal blooms
- Runoff (nutrients)

- Winslow, M. (2006). The heat is on*. Lake Champlain Committee Lake Look. *Retrieved November 11, 2007 from http://www.lakechamplaincommittee.org/cgi-bin/newspro/fullnews.cgi?newsid1158589838,15832

## acknowledgments

- Thesis Committee
- Dr. Monika Calef
- Dr. Doug Burns, USGS
- Dr. Andrei Lapenas
- NYSDEC

## contact

- _[kddello@gw.dec.state.ny.us](mailto:kddello@gw.dec.state.ny.us)_
- 								NYSDEC
- 625 Broadway
- 						Albany, NY 12233-3502
- 							ph. 518-402-8166