Reply on CC1

The influence of the Atlantic Multidecadal Oscillation and other well known modes of variability are discussed for Africa. What role do parameters such as Southern Annular Mode (SAM), AMO or ENSO play for SAMS in South America?

While we do compare proxy records and isotope-enabled climate models, our analysis is not focused on trends in the records or in the Principle Component time series. Instead, our results examine the South American Summer Monsoon during the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA), two periods during which the SASM exhibits multi-centennial departures from its mean state (Campos et al., 2019). The comparison is focused on the mean δ 18 O values in paleoclimate records and the isotope-enabled climate model during these periods. Our results in Figure 5 show that the proxies and isotopeenabled models show consistent mean state departures.  Figure 4 of that paper.
Figure 5a,f shows the precipitation patterns modeled during the MCA/LIA. This clearly shows which parts of the SASM region would be expected to get wetter/drier during these periods.

The influence of the Atlantic Multidecadal Oscillation and other well known modes of variability are discussed for Africa. What role do parameters such as Southern Annular Mode (SAM), AMO or ENSO play for SAMS in South America?
Though modes such as the SAM, AMO, and ENSO do contribute to South American climate variability, we do not discuss them directly in conjunction with our results because they do not emerge as leading drivers of the monsoon modes highlighted in this proxy-model comparison.
The influence of different SAM phases on SASM variability is derived from the changes in anticyclonic wave breaking activity within the southern jet. Transient cyclones migrate farther north during the negative SAM phase relative to the positive phase, enhancing baroclinic activity in the South Atlantic Convergence Zone and the local precipitation anomalies (Kodama, 1993

The ENSO influence on the SASM is most notable on interannual timescales. In observations and in annually resolved and precisely dated archives, the ENSO signal can easily be identified in the isotopic composition of precipitation (Vuille and Werner, 2005; Hurley et al., 2019). These studies show that the influence of ENSO is indirect, via modulation of the monsoon mean state through
perturbations of the Walker circulation, rather than directly affecting the precipitation or temperature at the proxy sites. However, the paleorecord network analyzed in this study does not have the temporal resolution nor the dating precision required to capture the ENSO signal on these timescales.
Can you illustrate all isotope proxy records individually in the Supplement? It would be good to see how uniform or different these individual records are.
All the isotope records used in this analysis have been previously published (apart from the MV record) and are accessible in their original publications. Furthermore, the isotopic time series of the proxy network generated in the MCEOF analysis have already been published (see supplemental information in Campos et al., 2019). We encourage the interested reader to seek out this publication for further detail. There exist no continuous high-resolution temperature records covering the last millennium from this part of the world, and no records that document temperature during the MCA in particular. Our analysis of the MCA and LIA documents departures from the mean hydroclimate state of the SASM. This is not related to temperature, as temperature changes can not explain the observed isotopic excursions seen in tropical South American proxy records over the past millennium (see discussions on this aspect in Bird et al., 2011;Hurley et al., 2019).