In this paper, we consider climate change as a systemic respiratory crisis, and explore how breath can function as a mode of witnessing climate catastrophe. We build on feminist environmental humanities methodologies of embodied attunement to advance a more-than-human witnessing of climate change. We suggest that a feminist “conspiratorial” witnessing of breath(lessness) can afford an embodied, situated, empathetic and systemic mode of witnessing. In this approach, the witness (e.g., “the human”) is part of what is witnessed (the climate crisis). As (...) such, breathing climate catastrophe can reveal the intimate, visceral and personal violences of global climate change, and develop empathetic approaches to climate injustice. Nevertheless, as breath’s social and multispecies differentiation reveals, no-one can witness the entirety of climate catastrophe with their own bodies. We thus advocate for collective, more-than-individual modes of knowing, such as science, art and critical analysis, to augment our own sensorial experiences of witness. (shrink)