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Joy Clein, A. David McGuire, Eugenie S. Euskirchen, and Monika Calef

simulations, we compared the mean monthly and interannual variability of three carbon fluxes simulated by TEM: 1) net primary production (NPP), 2) heterotrophic respiration ( R h ), and 3) net ecosystem production (NEP). We also compared cumulative changes in vegetation, soil, and total carbon storage among the three simulations. To evaluate one of the conclusions of Kimball et al. ( Kimball et al. 2007 ), we compared how the ratio of vegetation to soil carbon is changing through time among the three

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Shizuo Suzuki, Masayuki Yokozawa, Kazuyuki Inubushi, Toshihiko Hara, Michitoshi Kimura, Shoichi Tsuga, Yasuhiro Tako, and Yuji Nakamura

wetland environmental conditions. The objectives in this paper are 1) to estimate CO 2 exchange rates [net ecosystem productivity (NEP), gross primary productivity (GPP), and ecosystem respiration rate ( R e )] of the introduced wetland in the CGEF and 2) to investigate the factors governing the CO 2 exchange rates. 2. Materials and methods a. Introduction of a wetland ecosystem into the CGEF The CGEF includes a geosphere module (GM) and a geosphere material circulation system (GMCS). The roof and

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Philip R. Thompson, Mark A. Merrifield, Judith R. Wells, and Chantel M. Chang

of change across the basin ( Fig. 1 ). The global mean rate during the altimeter period (1993–present) is about 3 mm yr −1 (e.g., Nerem et al. 2010 ). Rates in the northeast Pacific (NEP), however, are near zero or negative ( Bromirski et al. 2011 ), whereas rates in the western tropical Pacific (WTP) are up to 3 times larger than the global rate ( Merrifield 2011 ). Fig . 1. Linear rates of sea surface height change measured by satellite altimeters shown with annually averaged coastal sea

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C. Potter, S. Klooster, P. Tan, M. Steinbach, V. Kumar, and V. Genovese

considers not only actual vegetation types, but also the historical changes in land cover properties and vegetation type at each pixel location using satellite remote sensing. In addition, the effect of simultaneous plant, soil, and climate impacts can be captured in the physiological process description, which is uniquely valuable in a domain where there is still a sparse distribution of long-term field study sites of these effects from which to gather net ecosystem production (NEP) data for

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Shuqin Zhang, Gang Fu, Chungu Lu, and Jingwu Liu

distinct high-frequency centers that are identified above; hereinafter we refer to them as the Japan–Okhotsk Sea (JOS), the northwestern Pacific (NWP), the west-central Pacific (WCP), the east-central Pacific (ECP), and the northeastern Pacific (NEP). The boundary between JOS and NWP ECs is the Japan Islands, Kuril Islands, and Kamchatka Peninsula. The boundaries for distinguishing other regions are determined by using two principles: 1) The dividing lines must be simple enough to distinguish ECs and 2

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Mengrong Ding, Pengfei Lin, Hailong Liu, and Fei Chai

that the decadal variability of EKE in the KOE region is primarily due to the barotropic flow instability, which is related to the NPGO. However, few studies have focused on the relationship between the long-term variability of eddy activity and large-scale climate modes in the northeastern Pacific (NEP) region (20°–60°N; 180°–130°W, i.e., the purple rectangle in Fig. 1a ), where large variances of both the PDO and NPGO happen. Fig . 1. (a) Bathymetry of the North Pacific basin from the ETOPO5

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C. Potter, S. Klooster, P. Tan, M. Steinbach, V. Kumar, and V. Genovese

remote sensing. In addition, the effect of simultaneous plant, soil, and climate impacts can be captured in the physiological process description, which is uniquely valuable in a domain where there is still a sparse distribution of long-term field study sites of these effects from which to gather net ecosystem production (NEP) data for continental-scale interpolations. The National Aeronautics and Space Administration Carnegie Ames Stanford Approach (NASA-CASA) model is designed to estimate monthly

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Christopher Potter, Steven Klooster, Alfredo Huete, and Vanessa Genovese

( Potter et al. 1993 ). This model calibration has been validated globally by comparing predicted annual NPP to more than 1900 field measurements of NPP ( Figure 1a ). Interannual NPP fluxes from the CASA model have been reported ( Behrenfeld et al. 2001 ) and validated against multiyear estimates of NPP from field stations and tree rings ( Malmström et al. 1997 ). Our NASA-CASA model has been validated against field-based measurements of NEP fluxes and carbon pool sizes at multiple boreal forest sites

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Jingfeng Xiao, Qianlai Zhuang, Eryuan Liang, Xuemei Shao, A. David McGuire, Aaron Moody, David W. Kicklighter, and Jerry M. Melillo

temperature ( Kirschbaum 1995 ), although acclimation of these processes may exist ( Luo et al. 2001 ). Finally, drought affects net ecosystem productivity (NEP) by directly or indirectly affecting photosynthesis and R H . In spite of this knowledge, historical droughts are rarely examined explicitly in carbon cycle studies at regional or global scales. Studies on the effects of drought on ecosystem carbon fluxes have been based on short-term/seasonal observations and modeling ( Law et al. 2001

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Hyacinth C. Nnamchi and Jianping Li

Previous studies using the EOFs, singular value decomposition (SVD), and composite analyses demonstrate that there are two centers of action of opposing SST variability in the SAO ( Venegas et al. 1996 , 1997 ; Trzaska et al. 2007 ; NLA11.). One center is located in the northeastern (10°E–20°W, 0°–15°S) and the other in the southwestern (10°–40°W, 25°–40°S) parts of the SAO. These are respectively referred to as the northeast pole (NEP) and southwest pole (SWP) of the SAO. NLA11 defined the SAOD

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