Figure 1: Correlations between modelled precipitation δ18O and PNA index.
From: Paired oxygen isotope records reveal modern North American atmospheric dynamics during the Holocene
Maps show long-term (1950–2005) correlations between IsoGSM precipitation δ18O and PNA index (Climate Prediction Center) in the North American (NA) continent. (a) Cool season (December–March) correlation. (b) Annual correlation. The areas enclosed by the grey line show significance at the P<0.1 level. Both cool season and annual correlations display a northwest (NW)–southeast (SE) dipolar pattern across the NA continent, with positive correlation in the NW and negative correlation in the SE. Numbers indicate locations mentioned in the text: 1—BCC speleothem14, 2—OCNM speleothem15, 3—Lake Grinnell16, 4—Lake Jellybean10, 5—Crawford Lake29, 6—Castor Lake25, 7—Little Salt Spring24, 8—Estancia Lake23, 9—Crevice Lake26, 10—Dog Lake27, 11—Felker Lake28.
