NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory
High-latitude systems in northwestern Canada and Alaska have warmed rapidly. The aim of this study was to examine how a remotely sensed proxy of vegetation productivity varied among mountain ranges with respect to elevation and climate from 2002–2017. Our study area included high-latitude mountains...
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| Format: | Article |
| Language: | English |
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Taylor & Francis Group
2019-01-01
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| Series: | Arctic, Antarctic, and Alpine Research |
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| Online Access: | http://dx.doi.org/10.1080/15230430.2019.1650542 |
| _version_ | 1818163136697466880 |
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| author | David Verbyla Thomas A. Kurkowski |
| author_facet | David Verbyla Thomas A. Kurkowski |
| author_sort | David Verbyla |
| collection | DOAJ |
| description | High-latitude systems in northwestern Canada and Alaska have warmed rapidly. The aim of this study was to examine how a remotely sensed proxy of vegetation productivity varied among mountain ranges with respect to elevation and climate from 2002–2017. Our study area included high-latitude mountains in Alaska, USA, and Yukon Territory, Canada, ranging from cold arctic mountains in the tundra biome to warmer interior mountains areas within the boreal biome. We used the annual maximum Normalized Difference Vegetation Index (NDVI) data from the 250-m MODIS NDVI product as a proxy of maximum growing season photosynthetic activity. The long-term (16-year) and interannual pattern of maximum NDVI was investigated with respect to elevation, July temperature, and July precipitation classes within four climatic mountain regions. The July temperature lapse rate was consistently linear, whereas the long-term maximum NDVI lapse rate was nonlinear. At lower elevations, the high-precipitation region had the highest NDVI, whereas the interior mountains region had the highest NDVI at higher elevations. The long-term maximum NDVI was negatively correlated with July precipitation for areas with July temperature below 12°C. Above 12°C, NDVI was positively correlated with July precipitation, with the greatest rate of NDVI increase with precipitation at the warmest July temperature class. The pattern of interannual peak NDVI with respect to July temperature was not as strong as the long-term pattern; however, the only interannual negative correlation between peak NDVI and July temperature was at lower elevations within the interior mountains. We concluded that among a regional climatic gradient of mountain areas, low growing season temperature and length were likely constraining vegetation productivity, and lower growing season moisture may be an important constraint at the warmest interior mountains region. |
| first_indexed | 2024-12-11T16:44:46Z |
| format | Article |
| id | doaj.art-31a6335ed3bc408f869a77bc472e4ce8 |
| institution | Directory Open Access Journal |
| issn | 1523-0430 1938-4246 |
| language | English |
| last_indexed | 2024-12-11T16:44:46Z |
| publishDate | 2019-01-01 |
| publisher | Taylor & Francis Group |
| record_format | Article |
| series | Arctic, Antarctic, and Alpine Research |
| spelling | doaj.art-31a6335ed3bc408f869a77bc472e4ce82022-12-22T00:58:15ZengTaylor & Francis GroupArctic, Antarctic, and Alpine Research1523-04301938-42462019-01-0151139741110.1080/15230430.2019.16505421650542NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon TerritoryDavid Verbyla0Thomas A. Kurkowski1University of Alaska FairbanksUniversity of Alaska FairbanksHigh-latitude systems in northwestern Canada and Alaska have warmed rapidly. The aim of this study was to examine how a remotely sensed proxy of vegetation productivity varied among mountain ranges with respect to elevation and climate from 2002–2017. Our study area included high-latitude mountains in Alaska, USA, and Yukon Territory, Canada, ranging from cold arctic mountains in the tundra biome to warmer interior mountains areas within the boreal biome. We used the annual maximum Normalized Difference Vegetation Index (NDVI) data from the 250-m MODIS NDVI product as a proxy of maximum growing season photosynthetic activity. The long-term (16-year) and interannual pattern of maximum NDVI was investigated with respect to elevation, July temperature, and July precipitation classes within four climatic mountain regions. The July temperature lapse rate was consistently linear, whereas the long-term maximum NDVI lapse rate was nonlinear. At lower elevations, the high-precipitation region had the highest NDVI, whereas the interior mountains region had the highest NDVI at higher elevations. The long-term maximum NDVI was negatively correlated with July precipitation for areas with July temperature below 12°C. Above 12°C, NDVI was positively correlated with July precipitation, with the greatest rate of NDVI increase with precipitation at the warmest July temperature class. The pattern of interannual peak NDVI with respect to July temperature was not as strong as the long-term pattern; however, the only interannual negative correlation between peak NDVI and July temperature was at lower elevations within the interior mountains. We concluded that among a regional climatic gradient of mountain areas, low growing season temperature and length were likely constraining vegetation productivity, and lower growing season moisture may be an important constraint at the warmest interior mountains region.http://dx.doi.org/10.1080/15230430.2019.1650542alaskaalpine tundraclimate warminggridded climatehigh latitudemountain classndvisummer warmthlapse rateyukon |
| spellingShingle | David Verbyla Thomas A. Kurkowski NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory Arctic, Antarctic, and Alpine Research alaska alpine tundra climate warming gridded climate high latitude mountain class ndvi summer warmth lapse rate yukon |
| title | NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory |
| title_full | NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory |
| title_fullStr | NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory |
| title_full_unstemmed | NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory |
| title_short | NDVI–Climate relationships in high-latitude mountains of Alaska and Yukon Territory |
| title_sort | ndvi climate relationships in high latitude mountains of alaska and yukon territory |
| topic | alaska alpine tundra climate warming gridded climate high latitude mountain class ndvi summer warmth lapse rate yukon |
| url | http://dx.doi.org/10.1080/15230430.2019.1650542 |
| work_keys_str_mv | AT davidverbyla ndviclimaterelationshipsinhighlatitudemountainsofalaskaandyukonterritory AT thomasakurkowski ndviclimaterelationshipsinhighlatitudemountainsofalaskaandyukonterritory |