North American rainfall and temperature prediction response to the diversity of ENSO

Weighting of NMME temperature and precipitation forecasts across Europe

“…Because of the large volumes of data that are produced within the NMME (Table 1), global-scale studies have focused on the evaluation of model skill at specific lead times Mo and Lettenmaier, 2014), or for specific seasons (Wang, 2014), models (Jia et al, 2015;Saha et al, 2014), or climate quantities (Barnston and Lyon, 2016;Mo and Lyon, 2015). Regional evaluations of NMME forecast skill have focused principally on North America (Infanti and Kirtman, 2016), the United States (Misra and Li, 2014;Roundy et al, 2015;Slater et al, 2017), the southeastern United States , but also China (Ma et al, 2015a(Ma et al, , 2015b, Iran (Shirvani and Landman, 2016) and South Asia (Sikder et al, 2015). Thus, most of the effort of the NMME model skill evaluation has been over the USA, and far less attention has been paid to Europe, with some exceptions, such as Thober et al (2015), who used NMME forecasts as input for the mesoscale hydrologic model (mHM).…”

CGCM and AGCM seasonal climate predictions: A study in CCSM4

“…In a climate prediction setting, Shukla [] showed that during the JFM1998 El Niño event, extratropical circulation was predicted with some skill even at a 6 month lead but would have been more accurate if the forecasted SSTs were closer to observed, indicating that SST biases impacted the prediction. In some regions, such as the southeastern U.S., prediction skill is highly sensitive to changes in SST, and skill can suffer due to errors in predicted SSTs [ Infanti and Kirtman , ]. In contrast, and when using persisted versus observed prescribed SSTs, Goddard and Mason [] found that in regions where skill is highly tied to El Niño, the skill was similar for both simulations but that SST errors led to losses in prediction skill in other regions.…”

Reconstructing El Niño Southern Oscillation using data from ships’ logbooks, 1815–1854. Part II: Comparisons with existing ENSO reconstructions and implications for reconstructing ENSO diversity

“…MCG10 noted that their reconstruction might be influenced by an over representation of North American tree rings due to the common use of these tree rings within the multiple reconstructions they used, as well as their higher weightings. This leads to a potential source of bias within their ENSO reconstruction as the temperature and precipitation teleconnections during EP and CP events differ in this highly weighted North American teleconnection region (McGregor et al 2010;Infanti and Kirtman 2016). Emile-Geay et al (2013b) showed that during the period coincident with the logbook-based reconstruction lower weightings were given to the tree-ring networks of North America, with highest weightings given to corals in the western Pacific, eastern Indian Ocean, Red Sea and a South American ice core.…”

“…Recent decades have seen an increase in the occurrence and strength of CP El Niño events, therefore it is important to understand the implications of these events (Lee and McPhaden 2010). Recent studies have identified some key differences in the teleconnections of EP and CP events, for example in the spatial patterns of temperature and precipitation anomalies over the USA, variables that influence ENSO reconstructions from tree-rings (Infanti and Kirtman 2016). The relationship with the western North Pacific monsoon and ENSO is found to be weaker for EP events than CP events (Weng et al 2011) and Australian rainfall and Indian Monsoon rainfall is more sensitive to CP events than EP events (Wang and Hendon 2007;Kumar et al 2006).…”